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====== Guide to Atmospherics ======

This is the Guide to Atmospherics. When properly initialized, Atmosia can keep the station aired-up through nearly any emergency.  Improperly initialized, it's a waste of space at best and an outright fire hazard at worst.

If you're new to the job, feel free to jump straight to the How to set up Atmos section. If you're ready to really learn about the atmospheric system, read on. By reading this guide you will learn how to transform Atmos from a waste of space to an actually useful addition. We will go through all kinds of theory, so this may be tough, but it will also ensure you know exactly how and more importantly why Atmos works the way it does, making you ready for all kinds of situations.

=====The Gases and Their Functions=====
Let's start with some theory about the gases. Below are the different gases that can be found in game.

====O2====
Oxygen. All humans, pets and most other people and creatures need more than 16 kPa of oxygen in the air or internals to breathe. Any less and the creature starts to suffocate.

It is required to oxidize a plasma fire. A room with 100% plasma will not burn. More oxygen causes plasma fires to increase in heat and size. Oxygen mixed suddenly with heated plasma causes explosions. See Temperature.

Oxygen is an invisible gas. To detect it, use your PDA or a wall mounted Air Alarm. Oxygen canisters are marked in blue. Emergency Oxygen Tanks, filled with about 300 kPa, spawn in your emergency Internals Box. Larger Oxygen Tanks are in Emergency Lockers all across ship, which start with about 600 kPa.

====N2====
Nitrogen. Soaks up heat in the air, and lowers the temperature of a fire. By association, it can very quickly lower the temperature of a fiery rupture to the point where the flames self-extinguish.

Proof of this can be seen if you go down to the incinerator with a can of burnmix, and a can of 20% burnmix and 80% N2. The N2 contaminated fire will not burn nearly as hot or as well. This is why the Toxins guide recommends opening up a can of N2 to the air; it can and will save your life if there's a rupture.

Due to the vastly higher heat capacity, N2 is incredibly better at stopping fires: in 100 kPa of N2/O2 80/20 and 100 kPa of 100 % O2, the N2/O2 is effectively 12200 kPa as opposed to 100 kPa in terms of soaking up heat and it doesn't allow the fire to grow in size as quickly, the combination of which can even lead to non-permanent ignition sources being snuffed out by themselves.

Can be found in Atmospherics in red canisters.

====Air====
A 1/5 gasmix of O2 and N2 (20% O2, 80% N2). Most stations and starships are typically filled with this.

Air in SC13 can be seen, strangely enough, as a 'watered down'-O2, with N2 being the water. Optimal atmospheric pressure for humans is 101.3 kPa. Due to the minimum of 16 kPa of O2, the pressure of 101.3 kPa cannot be changed too much without the situation becoming excessively lethal. Under 16 % oxygen? You start dying. Under 90 kPa due to fire from a while ago? You start dying. Be mindful of this.

Air canisters, marked in white, can be found in emergency storage.

====CO2====
What the fuck is Carbon Dioxide!?  It's an invisible, heavy gas. CO2 is one of the first and easiest gases the scrubbers suck out of the air. Humans produce very small amounts of CO2 through breathing, and normal plants inhale very small amounts of CO2 as they grow.

It chokes people effectively and quickly, and if you can be bothered to set the alarms up, will result in a invisible room that kills those in it. Takes some setup and can be very, very annoying. Causes people to gasp at low levels.

Can be found in Atmospherics in black canisters.

====N2O====
Nitrous Oxide, a.k.a. Sleeping Agent. A white-flecked gas.

Makes you laugh at low doses and at higher ones puts you to sleep. Scrubbers don't deal with it too well and portable scrubbers just choke on it. If using this as a sleep gas mix do not forget to mix in at least 16 kPa of O2, or you will suffocate someone.

Can be found in Atmospherics in red canisters with a white stripe on them.

====Phoron====
Toxins. The one truly flammable gas on the station, plasma is purple, and highly toxic.

Of note is the fact that in the presence of any oxygen at high pressures, Plasma pumped into air, and Burn Mix (O2 and Plasma), can and will spontaneously ignite in an open area at high pressures.

====BZ====
BZ gas is a potent hallucinogenic. Its only constructive use is as a slime suppressor, but it can be used by some less than scrupulous crew members to create chaos and raise hell throughout the station. Dragging a purple BZ canister through the halls is easily noticed, so you may want to transfer it into an empty oxygen canister. Unupgraded atmospherics scrubbers do not have a setting to remove BZ, so there's no defense outside of using other internals before inhaling it.

If mixed in a tank with oxygen, it can be used for internals, to encourage spiritual development.

====Freon====
A high-power coolant gas. When released, it will cool down the air around it, lowering the temperature, freezing the ground causing it to become slippery, and making any item exposed to it extremely brittle and prone to breaking if thrown. People exposed to freon may also end up encased in ice cubes, trapping them until they resist out or are thawed.

Currently it is mostly used as engine coolant, for supercooling certain special rooms, or for when you want to fight fire with something worse.

=====Physical Characteristics of Gases=====
Ideal gas law: PV = nRT

Where R (ideal, or universal, gas constant) = 8.31,  the following are linked by this equation. 

**Pressure (P):** Measured in kPa, [http://en.wikipedia.org/wiki/Pascal_(unit)|kiloPascals], Pressure is lethal above 750 kPa's. 

**Volume (V):** Another unseen variable, [http://en.wikipedia.org/wiki/Volume|Volume] is how much the area/canister/tank or piped tank has space inside it. This helps dictate how much gas it can hold. Volume is essentially the 'mole divider' when converting between a canister/air pump to your tank; having a higher volume essentially makes the tank that much more efficient, proportionally, so an Extended Emergency Oxygen Tank has twice the contained air per kPa in comparison to a regular Emergency Oxygen Tank.

Emergency Oxygen Tank: 3

Extended Emergency Oxygen Tank: 6

Oxygen Tank (blue/red): 70

Plasma Tank: 70

All pipes: 70

Pipe manifold: 105

Locker: 200

Coffin: 200

Gas Pump (each side): 200

Volume Pump (each side): 200

Passive Gate (each side): 200

Heat Exchanger: 200

Gas Filter: 200

Vent: 200

Scrubber: 200

Portable Scrubber: 750

Gas Canister: 1,000

Tile / turf (any area): 2,500

Portable Pump: 1,000

Unmovable pressure tank: 10,000

Huge scrubber: 50,000

Moles (n): While not a variable that can be seen, [http://en.wikipedia.org/wiki/Mole_(unit)|Moles] are the amount of particles of a gas in the air. It is moles that cause odd effects with a certain chemical. As it dumps so many moles to a tile, to keep the pressure acceptable, the moles have to be very, very cold, causing the infectious effect. Moles can be calculated by a form of the ideal gas law. n=(P*V)/(R*T)

Temperature (T): Measures in K, [http://en.wikipedia.org/wiki/Kelvin|Kelvin], Temperature above 360 K and below 260 K causes burn damage to humans. Bomb making usually relies on a temperature at or in excess of 90,000 K. Canisters rupture when the air surrounding them is over 1550 K.

Heat Capacity: A gas mix has heat capacity, and it is calculated by taking into account the quantity of all of the gases in the air and their specific heat. Oxygen has a specific heat of around 20, CO2 has 30, and N2 has 300. When you factor in the normal 70% N2 it leaves you with a very high specific heat. The higher the specific heat, the more energy required to heat up the mixture, meaning that with an air mix vs. pure O2 mix, it takes much more energy to heat the air than the O2, and the increase in energy required also decreases how much a fire spreads. Simply slowing it down means that heat energy will be 'soaked up' by the air instead of super-heating everything extremely quickly. 
  * O2: 20
  * CO2: 30
  * N2O: 40
  * Phoron: 200
  * N2: 300

Fire: An effect usually caused by burning plasma, fire comes in two different forms of hotspot. It causes massive burn damage, and a strong fire will not be stopped by standard firesuits. Plumbing N2 into a room might work, but heavy firefighting is not the point of this section. Fire will ignite any form of combustibles in nearby tiles. Sufficiently hot fires use less oxygen as they rise in temperature. This is due to the fact that fires remove X plasma and X*(1.4-Y, Y< or = 1) oxygen. X CO2 is produced. Ideal Burnmix is: 10x more O2 than plasma, and with as high a temperature as can achieve.


=====Atmospherics Layout=====

Atmospherics is pretty simple, but the pipe layout makes it slightly confusing for the untrained eye.

There are 4 major pipe "loops":
  * The dark blue pipe loop is the distribution loop. It sends air to all the vents on the station for the crew to breathe.
* The cyan air mix pipe loop, which is specialized to mix and provide the air mix to the distribution loop, and is used to fill air pumps outside the front door of Atmospherics.
  * The red/green pipe loop, which retrieves the gas in the station via the air scrubbers (red loop) and passes them through a set of filters (green loop).
  * The yellow pipe loop, internal to Atmospherics, which is used for custom gas mixes that can be fed into the canister charging station in the middle of atmospherics, or fed into the mixing tank.

Atmospherics uses huge, unmovable pressure canisters or multiple-tile 'room' tanks to store the gas needed to maintain air pressure and quality. The output of these canisters are controlled by their respective Supply Control Computer, an on/off valve, and an output pump for each loop. Note that these canisters can be depleted, especially if someone makes a hole in the pipe.

To understand how the breathable air mix is mixed, try following these steps and looking at the map at the same time. It starts on the south end of Atmospherics, like so:
  * The gasses are pumped through the cyan tubes from their respective tanks (N2, O2).
  * They are mixed in the air tank (Air) to a 1/5 mix of O2 and N2.
  * The breathable gas is then pumped through the cyan loop to the north of Atmospherics.
  * And finally it's pumped into the dark blue distro loop and out to the station for everyone to breathe.

Next let's make up an example situation to see how the waste system works in action:

  * Scientist Bill messes up and fills the Toxins Lab with phoron but fortunately manages to evacuate the room safely.
  * Being an otherwise ideal situation Atmos-wise, the Toxins Lab's air scrubbers have been set to filter out all hazardous gases (they're not set by default; this has to be done through the Air Alarm manually or by asking the AI to do it) and phoron starts to get sucked through the scrubber into the waste pipes.
  * The plasma arrives to the Waste In-loop (the red pipe loop) at Atmos. It travels south through the pipes, its first stop being the N2 Filter.
  * If there was any Nitrogen in the waste gas, it would get filtered out here, and the rest of the gas continues its journey through the waste loop, with the same thing happening at every filter.
  * The phoron finally reaches the Phoron Filter.
  * Here the phoron gets extracted from the waste gas and pushed into the big phoron canister.
  * The phoron stays in the canister until someone decides to pump it out.
  * Scientist Bill by now notices that the Toxins Lab has no plasma anymore and is able to safely continue his work. Yay!

=====Setting Up Atmospherics=====
It's about time we stop with the theory and get down to business. The two machines at the top can dispense infinite pipes, and your wrench can disconnect and connect pipes to each other. Remember, you cannot disconnect pumps if they have too much pressure in them.

Next up is a very simple step by step guide how to set up the Atmospherics pipe system to be (nearly) as efficient as possible. Note that this is only one way to set up the pipes; there are many ways and they all have their own pros and cons!

  * For the love of NovusCorp, at least do this:
    * Get a Volume Pump from the [[Pipe Dispenser]] at the north side of Atmos and replace the normal pump with a volume pump, making the waste gas system >100x more efficient. We want the waste gas sucked from the station into the waste system as soon as possible!
    * Set all filters ON and set them to maximum pressure (4500 kPa) so waste gases will actually be moved.
  * This is good as well:
    * Go through the N2 and O2 (beside southern wall) and set their output to 4500 kPa.
    * Set the pumps next to the computers at 4500 kPa also, so the gases pushed out of the canisters are being moved fast too.
    * Set the Air-computer's output to maximum (5066.25 kPa).
    * Replace the normal pump with a Volume Pump as well, but notice; there are risks involved and all of them are covered at the pros and cons section below.

Pros and cons of this whole setup:

  * Quick toxin filtering: In case of a toxin leak, waste gas will be sucked out quickly (if the area's air alarms are set to filter out all the toxins, that is, by default they are NOT filtering anything).
  * Quick repressurization: In case of a breach, air will be poured out with a nice pace, helping you repressurize the room quicker after the breach is fixed.
  * Reduced pipe sabotaging: With this setup, its harder for the grifflords to fuck up pipes in the maintenance tunnels. In a room with the default 101.3 kPa atmospheric pressure, pipes with more than 303.9 kPa pressure fling the unwrencher in a random direction.

  * Air Alarm sabotages: The station is more vulnerable for sabotage through air alarms. Someone can quite easily hack an air alarm somewhere and set the vents to push out air at maximum pressure, resulting in overpressurization.
  * Space wind: In case of a breach, until the hole is fixed, you'll probably spend a small while fighting against the huge air current, a.k.a. "space wind", if you don't switch the vents off during the repair. This is mostly just annoying.
  * Very slow pipe manipulating: If you suddenly have to modify any of the distribution pipes around the station, you need to lower the pressure to under 303.9 kPa if you don't want to be flung around like a leaf in the space wind, which can take a long time.

A little safer, but not as efficient, way of setting up the system is leaving the air mix normal pumps completely alone or maybe raising the pressure to 315 kPa. This pressure is enough for quick pipe manipulating and for a sufficient air distribution.

Done correctly, Atmosia should be pumping good air just faster than it's lost, and draining bad air away as fast as the traitors can set it on fire or alternatively draining good air away as fast as a malf AI can syphon it. You can go kick back in the bar like a boss, and wait for the inevitable minor ship damage and cries of "Call the shuttle!" on the radio from folks who don't even know it ain't a big deal.

=====After the Work is Done=====
There is a short list of things which fall under your stead:
  * First and by far most important: make sure pipes don't get broken and if they do, fix them.
  * Go around swiping your ID on Air Alarms, setting Plasma and N2O to filter, and then re-swiping to lock it. You can ask the AI to do this as well, and probably should.
  * Fill all the air pumps with air using a volume pump (more air pumps can be found from the locker room).
  * Make extreme extended oxygen tanks for internals use (instructions below).
  * Go to the red lockers, get a hard hat, gas mask and everything else that might be of use. Remember that you need both a fire suit and a hard hat to be resistant to weak fires. One will be useless without the other.
  * Upgrade the Air Alarms, allowing them to purge more gases and smokes from the system; this will prevent the really clever bastards from blasting the crew with their chosen hellmix, or at least put a significant damper on it if they're not savvy enough to check the Air Alarm setup first.
  * Go grab the Fire Axe from the wall mount and hide it somewhere the chucklefucks won't get it and go killing. DON'T take it with you and go walking through the hallways trying to look like a badass, you'll be the prime target of any antagonist/griffon who needs an efficient weapon.
  * Least importantly, maintain the disposals system. You can generate pipes for it as well, but it needs welding and is generally a pain in the ass. You can also make fun slides, though.

====Optimizing Internals====
  * On a basic view, a 16 kPa minimum O2 requirement in internals. Pure O2 is theoretically toxic in real life, but bioroids are immune to this problem, and O2 takes a while to be really dangerous anyway (they use it to treat certain diseases, for example), and thus using a tank filled with air for internals is fairly inefficient.
  * Cold O2 has more moles per kPa, and because people breathe in moles, and filling tanks usefully for internals is largely capped by the 1000 kPa release pressure, this means cooling your O2 before using it in internals is important! Cooled down O2, such as from a freezer-ed canister, is the most efficient way to set up internals. Cooling it below 264 K will result in icicles inside in your lungs, though!
  * If you need to empty an internal tank to make space for better, colder O2, you can use an Air Pump. Set it to "pump in" and "turn on" then "off" with the tank inside it, making it completely empty, thus allowing you to refill the tank more effectively.
  * An emergency oxygen tank with normal settings lasts for about 12 minutes. Same tank, but with optimized gas temperature and output settings reduced, lasts about 50 minutes. If you don't have resources to get cooled O2 right now, at least set your output pressure to the minimum of 16 kPa, it will give you 31 % more time to breathe.

====Your Very Own Customized Mix====
To create a custom mix of gas, turn on the output of the supply control computers, open the manual valves, and turn the output of the pump to what you wish it to be. The gas will travel through the orange pipes into the mixing chamber. The gas mix is pumped into the mixing chamber via a pump north of the orange loop.

The mix obtained can then be pumped into the distribution and filtering loop or used to fill canisters. Remember to turn off the pump between the yellow and red pipe network or your custom mix will just go into the red waste loop.


====Fun Projects====
  * The Atmospherics system is far from optimal, and we're talking about just the pipe configuration! Break out that wrench and start experimenting (just make sure you know what's what)!
  * Extremely high temperature gases (like those from a panic siphoned fire) can really clog the waste loop. Could you do something to correct that?
  * No one uses the ports outside of the 'refilling' station, but that doesn't mean that functionality can't be added onto them!
  * The wall section that looks like the letter 'I' can be dismantled if you need more working space for pipes.
  * Don't count out the grated window areas, they can be a great (har har) way to utilize the vacuum of space without an EVA suit.
  * Speaking of EVA suits, your engineering buddies can potentially help you with anything you might want to do in space, be it adding or modifying pipes. Watch the hilarity as that incompetent engineer fumbles with the huge crate of pipes he dragged out into space for you!
  * The main cargo area inside Cargo has a laughably small number of vents, and how many times have those dumb dumbs sent the shuttle off while the doors are open?
  * The brig's distribution system is set up to be potentially independent of the rest of the ship's distribution loop; can similar redundancies be set up elsewhere on the ship or station?
  * The mining station doesn't have air recycling. Very long rounds might make this a problem for any miners working there.

=====The Less Well Known Hazards of Gases=====
  * Any gas at pressure over 1000 kPa will cause you to start suffocating as in a vacuum. You can just use internals, though.
  * N2O is invisible at low pressures. If you start giggling, put on your internals to avoid passing out.
  * Any gas can displace O2, and less than 16 (also useful for optimizing internals) kPa of oxygen starts the Oxyloss. CO2 can be removed with the scrubbers, but to get rid of N2 simply apply some way of removing gas from the air and adding O2. My personal favorite is 2 air pumps, 3 connectors and a Air Filter and a canister: 1 pump draws in, goes through the connection and filters N2 into the canister, and the rest to the other pump, which expels it. Can also be used for N2O which is only sluggishly scrubbed otherwise.
  * Pressures above 750 kPa do 10 brute DPS + 5 DPS for every extra 375 kPa above that mark, rounded off. Space suits completely block it all, but there is no other defense.

=====Useful Atmos Trivia=====
  * Using H/E pipes in space you can cool things down to a very low temperature very quickly. By making a cross with two of them you can have two on one tile, which is known as 'sequestral' cooling.
  * Air Filters on currently burning mixes can siphon out heated but PURE O2 and Plasma. Do the O2 first then the plasma, as there is less O2 in a fire and thus it functions faster. This (and H/E) allow you to reach really obscene temperatures.
  * Air Filters and H/E allow you to expose gases to the heat of fires (or their CO2 product) but keep/make them pure, allowing for hot N2O or similar.
  * Using a small starter flame/heater you can have in-pipe combustion.
  * Canister bombs are simply heated Plasma in a canister, with a O2 tank placed in the canister, and then open the valve between them. You will also need to run very, very fast.
  * The gas diverted by an air filter has no maximum pressure, and can therefore reach an insane amount. For example, you can filter out the oxygen into one sealed pipe and it will keep rising.
  * Pipes at around 300 kPa pressure can't be unwrenched; however, devices such as pumps and filters don't really 'hold' pressure and can be unwrenched at any time (assuming they're off)!
  * Gas pumps are for precise pressure control, volumetric pumps are for really fast pumping, and passive gates are for having 'one way' manual valves.

=====Being a Traitorous Scum=====
Or: How to evacuate the station/ship/get the AI lynched as an Atmos Tech, step-by-step:
  * Open valves connected to harmful gasses you want to add to the station.
  * Set pumps to the distribution loop to maximum pressure output (4500 kPa).
  * Set filters to not filter harmful gasses you want to add to the station OR set the waste-in pump to 0 kPa (but leave it on to confuse the crew).
  * Open valve from custom mix chamber.
  * Turn on pump leading to distribution loop.
  * Wait for vents to slowly kick out your deathgas mix as regular atmos drains out through the inevitable hull breaches (alternatively turn off pressure checks on air alarms' vents to speed things up).
  * If you need to kill someone for your objective, and you want to be more proactive, the [[Fire Axe]] mounted in the wall is surprisingly effective. Just don't leave it lying around, because it's one of only two on the station.

To hurry this process up, you can set the air vents at local control panels to maximum output pressure. Not doing so gives the AI and Atmos Techs more time to notice what you've done and shut it off before it takes effect.

A faster process for achieving the same result is to do the following:
  * Disconnect, change the direction of, and reconnect the pump that feeds from the air mix to the mix tank in the north-eastern room of atmosia. 
  * Open the valves for your deathgas mixture of choice.
  * Power on and max the pressure on every pump in the mix pipes (yellow pipes) from the storage tanks out to the station output (blue pipes).

This simply means that instead of the air mix being put into the mix tank as it normally does, the air mix (which may or may not contain death gases) is fed into the ship output. 

Crafty atmos traitors will want to cut cameras, replace pumps with pipes, use tricky pipe configurations to avoid the AI interfering or a clever engineer trying to fix it, and make a hole in the ship's oxygen and air tanks, venting the entire round's supply of oxygen into space.

An extremely fast method that involves a clever use of the waste system is the following:
  * Reconfigure the piping to connect the waste system directly into the pure pipes.
  * Find a place with a waste pipe next to a distro pipe, then configure them so that they can be united later.
  * Open the valves for your deathgas mixture of choice, the waste piping should now begin to fill with your gases.
  * Set as many air alarms as you can to have every vent at Internal 0.
  * When ready, go back to your distro/waste pipe spot and unite them.
  * Listen to screams over the radio.

Other antagonistic things to do:
  * You can hack an air alarm to use it as a non-Atmos Tech.
  * You can C4 the digital valves to let you remove them and shut down AI control, or save a C4 and disable the cameras if you know there's no Cyborgs on the station.
  * Using a gas filter turned on to pour large, ever increasing, amounts of gas onto a single connector port has no visible effects, but if you wrench a canister onto it then the canister will almost immediately fill up with the massive pressure buildup, letting you get super-high pressure plasma/CO2/etc canisters to hit areas with.


Contents
1	Atmospherics 101: Basic Theory, Layout, and Custodian of The Air
1.1	The Standard Pipes
1.2	The Atmos Devices
1.2.1	Digital Valve
1.2.2	Pressure Valve
1.2.3	Manual Valve
1.2.4	Pressure Pump
1.2.5	Volume Pump
1.2.6	Passive Pump/Gate
1.2.7	Unary Vent
1.2.8	Passive Vent
1.2.9	Injector
1.2.10	Scrubber
1.2.11	Heat Exchanger
1.2.12	Filter
1.2.13	Mixer
1.2.14	Heat Exchange pipes
1.2.15	Heat Exchange Junction
1.2.16	Layer Adapter
1.2.17	Atmos Meter
1.3	Canisters
1.4	Stationary Tanks
1.5	Useful Tips
1.6	The Atmos Tools
1.6.1	Rapid Pipe Dispenser
1.6.2	Analyzer / BreathDeep Catridge
1.6.3	ATMOS Resin
1.6.4	ATMOS Holofan
1.7	Atmospherics Layout
1.7.1	Setting Up Atmospherics
1.7.2	Your Very Own Customized Mix
1.8	Atmospherics and The Station
2	Atmospherics 201: Gaseous Synthesis, Machinery, Further Theory, and Optimization
2.1	The Gases and Their Functions
2.1.1	O2
2.1.2	N2
2.1.3	Air
2.1.4	CO2
2.1.5	Plasma
2.1.6	N2O
2.1.7	Tritium
2.1.8	Water Vapor
2.1.9	H2
2.1.10	BZ
2.1.11	Pluoxium
2.1.12	Miasma
2.1.13	Nitrium
2.1.14	Freon
2.1.14.1	Hot Ice
2.1.15	Hyper-Noblium
2.1.16	Proto-Nitrate
2.1.17	Halon
2.1.18	Healium
2.1.19	Zauker
2.1.20	Helium
2.1.21	Anti-Noblium
2.2	Physical Characteristics of Gases
2.3	Optimizing Internals
2.4	Thermomachines
2.5	Fusion
2.6	Crystallizer
2.7	Bluespace Gas Vendor
2.8	After the Work is Done
3	Atmospherics 301: Pipeline and Pipenet Theory; LINDA: Active Turfs & Excited Groups; Superconduction
3.1	Pipeline and Pipenet Theory
3.2	LINDA: Active Turfs and Excited Groups
3.3	Superconduction
4	Being a Traitorous Scum
=====Atmospherics 101: Basic Theory, Layout, and Custodian of The Air=====
You, dearest atmospheric technician, have one main purpose: Keeping the station not too hot, not too cold, pressurized, and breathable. You might be able to synthesize difficult gases, but derelict this basic duty and you are not a good atmospheric technician.

====The Standard Pipes====
These days, pipes no longer have a set direction they connect in. Normal pipes will automatically connect with adjacent pipes of the same color and layer. The Omni pipes (grey colored) connect with ALL colors on the same layer. This is critical to keep in mind, as careless placement of pipes can result in accidental connections between previously separate pipenets. This feature is commonly referred to as "Smart Pipes". All pipes and pipe devices can be assigned colors, and even larger atmospherics machines also can have their color adjusted.

In the Rapid Pipe Dispenser (RPD) interface, you'll notice a few green arrow buttons on the left. These can be toggled off to restrict automatic pipe connections in a direction for the pipes you place. This is incredibly handy when working in tight spaces where there's no other way to avoid having two matching colored pipes pass each other. Pressing the circle button in the center will reset the restrictions to the default auto-connect.

If you need to connect two differing colors of pipes, a color adapter can be used in place of a regular pipe. However, an Omni pipe would work fine, as well as any device set to omni like a pump or valve.

====The Atmos Devices====
This will be a section detailing the overall function, and some specifics, of the various pipes, pumps, and other devices. Some details will be missed, but it will provide a basis. The first instance of a device running into a unique mechanic will be explained in further length.

===Digital Valve===
A valve that opens when clicked, and connects the two pipenets it separates when doing so. Counter to pumps, it experiences no delay in its gas transfer. It essentially acts as a pipe. Has 200L of volume on one side, and 200L on the other end. This can be operated by both carbon mobs such as humans, excluding xenomorphs, and silicons.

===Pressure Valve===
An activatable valve that lets gas pass through if the pressure on the input side is higher than the set pressure.

===Manual Valve===
Acts identically to a Digital Valve, however, the manual valve does not allow silicons to operate it.

===Pressure Pump===
An oddball case. Like all pumps, it separates connected pipenets if there is nothing else connecting them. Has a maximum pressure of 4500 kPa. All pumps work by pumping the contents within them to the other side, which is 200L on one side, and 200L on the other. Any pump can not pump gas that is not actually in it, which means that very large connected pipenets will have lower pump speeds. Pressure pumps work by gradually building up to its set pressure per tick. Because of this, pressure pumps slow down when approaching their target pressure, and will not quite match their pressure after a very long time, but will get very close.

===Volume Pump===
The volume pump is similar to the pressure pump, but operates differently. It has a pressure limit of 9000 kPa. However, this limit only kicks in when the output pipenet is currently over 9000 kPa. The pump will work if the output pipenet is below 9000 kPa, even if the resulting pressure of this action would be way higher than 9000 kPa. Counter to the pressure pump, this pump works on a L/s basis. This has a 2x200L volume as well, so you pick how much of the volume in the pump is actually pumped to the other side by changing the number. Because its max speed is 200 L/s, it will always outpace and outpressure the pressure pump. Can be overclocked using a multitool, which will cause its pressure limit to be dependent on the input pipenet, which will tend to make the maximum output pressure higher. However, this will cause 10% of gas running through it to spill.

===Passive Pump/Gate===
These are a combination of pumps and valves. They work up to their set pressure, with a maximum of 4500 kPa. These can never do more than equalize the two connected pipenets, just as valves do. However, they only work one way, rather than mixing the gas between the two pipenets perfectly as valves do. Think of them as a pressure pump that only equalizes pressure between two pipenets.

===Unary Vent===
The vent will pump gas into the room it is in, depending on the air alarm settings of the room. The air alarm has two settings to worry about, External, or Internal. External works by making the vent pump gas from its connected pipenet into the room until the room, or more accurately, the tile, matches the pressure that is set. The max pressure you can configure for External is 5066 kPa, and it slows down when approaching the set limit, as pressure pumps do. Internal works by pumping gas into the room from the pipenet until the pressure set matches the pressure in the connected pipenet. Examples: a vent set to External 200 will pump gas into the room until it is 200 kPa. A vent set to Internal 300 will pump gas into the room until the connected pipenet's pressure is 300 kPa, regardless of room pressure. As such, Internal 0 will always pump at full strength. This same effect can be achieved by turning off both External and Internal. The vent has a maximum speed it can pump at, even when extremely pressurised.

It should be noted that the vent can be made to suck gas as well, like the Scrubber below, when set to do so in the air alarm. It should also be noted that it does so faster than the scrubber, but it can not suck in gases in a 3x3, which means it loses in speed when the extra area matters and the pressure is low. The vent has no pressure limit when sucking in gas, which can be used to hilarious ends.

===Passive Vent===
An unpowered vent that equalizes the internal and external gases. Think of it as a simple open ended pipe into the atmosphere. It is not interactable and cannot be closed. It too, is not restricted by pressure as with the other vents, opening possibilities for interesting shenanigans.

===Injector===
The injector is similar to the vent in that it pumps gas onto the tile it is on. However, it is not controlled by an air alarm, but rather works by hand. It is also in L/s units again, similarly to the volume pump. Also similarly to the volume pump, it is the faster one when compared to its pressure based cousin, the vent. It does not have a maximum pressure change per second, as vents do, and will always outpace them. This comes at the cost of the control that vents give you.

===Scrubber===
The gas sucking cousin of the vent, which sucks gas into the connected pipenet. Scrubbers are operated using the connected air alarm. They only suck in gas that is on their tile, unless you set their range to Expanded, in which case it'll suck in a 3x3. Setting them to Siphon will make them suck in every gas. If the scrubber is not on siphon, you can select specific gases for it to suck into its pipenet. The more gases are selected to scrub, the more power is used. The scrubber has a pressure limit of 5000 kPa, and will not suck in gas when the connected pipenet is at or above this value. This is unlike the vent, which has no limit.

===Heat Exchanger===
Place two of these next to each other, facing each other, and they will equalize the temperature of the gases inside them. The heat exchanger is not part of the (more widely used) heat exchange pipes system.

===Filter===
The filter is the first device that connects 3 pipenets. It can be set to filter any number of gases, and it will dump them to the side it is pointing in. All gas that is not selected will continue straight forward, as the arrow is pointing in a single line. When set to Nothing, it will allow all gas through the straight path. The filter works in L/s, and as such does not experience pressure related slowdowns, however, it has a pressure maximum of 4500 kPa. When EITHER OUTPUT SIDE is 4500 kPa or above, the filter will not function, not allowing any gas to pass. That is, both in a straight line and on its offshoot, the pressure must be less than 4500 kPa.

===Mixer===
The mixer also requires 3 connections to function, as the filter does. The mixer will mix the two incoming gases using the ratio the user inputs, starts off at 50/50. Node 1 is the input in a straight line with the output, Node 2 is the offshoot compared to the output. Both inputs need to have gas in them to function unless a side with gas in it is set to 100%, in which case it will function and purely let that side through. Is pressure based, with the associated properties. Also has a pressure maximum of 4500 kPa. The mixing is influenced by temperature following the ideal gas law. When one of the input sides is hotter compared to the other input, it will let less of this side's gas through, mole-wise. This will give you scuffed ratios if you do not equalize temperatures, if you need the precision, make sure they're equal.

===Heat Exchange pipes===
Functions like regular pipe, however, this will attempt to equalize the temperature between the pipenet and the space it is in. This is based on heat capacity, which can be found on this page. Higher heat capacity means a gas will soak in more energy, which means it is better at cooling when cold, and better at heating when hot. These pipes commonly see use in Supermatter setups, to cool down the coolant by using these pipes in space. However, they can also be used to heat up places, of course. Has a 10K efficiency loss. Space is 2.7K, but heat exchange pipes will only cool the gas in them to be about 22.7K.

===Heat Exchange Junction===
These are used to transfer from normal pipes to heat exchange pipes. These need to be between a pipe, or pump, etc. and heat exchange pipes for gas to actually be transferred between the two different kinds of pipe. While this pipe looks partially like a heat exchange pipe, it does not equalize temperature in the way that heat exchanging pipes do. It only looks like it does, so these can be safely connected to any pipe in a normal room without risk.

===Layer Adapter===
Connects the different layers of pipenets (most stations have up to five by default). For most stations, the red scrubber network will be on layer 2 while the blue air supply pipes will be on layer 4. Default layer is 3. Pipes on different layers do not interact with one another.

===Atmos Meter===
Purple is freezing, green is room temp, red is scorching hot.

Normally attached to pipes, these useful devices can be read and examined to inform you of the value of both the pressure and the temperature of the contents within the pipe. From a glance, the visuals of the meter itself will adjust in response to said values, with the bar's color changing in response to temperature, and the length of the bar increasing in response to higher pressures. The lights will also fill in depending on how high the pressure is.

===Canisters===
These hold gases in a portable manner. However be VERY CAREFUL with them when you're dealing with hot gases or exothermic reactions (such as burnmixes, or even just freon formation), as they have pressure and temperature limits.

Canister frames may be made using 5 iron, Then completed by using 5 more iron on said frame. Canisters have a pressure limit of 500000kPa and a Temperature limit of 10000k.

Canisters have a shield that when turned on prevents gasses inside the canister from damaging it, allowing for extremely high pressures and temperatures as long as you have power; the higher the temperature and pressure inside, the higher the draw (it should peak around 25 kW). Power will be drawn from the nearest APC; otherwise it will use an internal battery. Power cells can be replaced by using a screwdriver to open the cover on the canister, then removing the battery with a crowbar.

===Stationary Tanks===
These are tanks that are immovable. They can be made by making a tank frame using 4 plasteel sheets and then using 20 sheets of a material of your choice on them. They have a volume of 2500L and a default pressure limit of 20000kPa. The pressure limit is affected by a material modifier, with glass giving 2000kPa and plasteel giving 30000kPa.

===Useful Tips===
Scrubbers, vents, injectors, valves, pumps, filters, and mixers can be safely unwrenched without spilling gas on a tile. Especially valves serve as a perfect alternative to a normal straight pipe, when wanting to be more safe with hot gas.

Most Atmospherics objects and machines can be operated with CTRL+click and ALT+click. CTRL+click will turn them on and off, ALT+click will max them out.

Panic Siphon on air alarms turns off all vents and sets scrubbers to Expanded range Siphoning. The contaminated setting will set the vents to normal atmospheric pressure, and scrubbers to Expanded range, and sucking in every gas that isn't Nitrogen or O2.

Pipes, vents, and other Atmospherics objects can be placed in walls! Most of the time, it is easier to dump gas into walls rather than trying to dump it in space. Even if the wall is destroyed or removed it will not spill the gas.

4-way Manifolds have the same volume as two pipes on top of each other, going north to south and east to west. Because of this, optimal usage of Heat Exchange pipes tends to be using a whole bunch of 4-way Manifolds.

Freezers and heaters can be placed directly on pipes, and they'll connect to it! Also, did you know that Freezers and Heaters can switch pipe layer by using a multitool on their board?

Because of the slow nature of pumps, they should be generally avoided unless looking for a specific purpose. Volume pumps are great for regulating speed consistently and pressuring pipenets because of their 9000 kPa limit. Pressure pumps are great for regulating pressure and slower gas movement, be creative!

Many, many things can be done using layer manifolds and different piping layers. No two ways about it, you'll have to experiment!

====The Atmos Tools====

===Rapid Pipe Dispenser===
This is your Rapid Pipe Dispenser. There are many like it, but this one is yours. The main tool of your trade, the RPD is what you use to generate new atmospheric devices. Use it in modifying the station's layout, in making new production compounds, in adding scrubbers and vents to various parts of the station, and much, much, more. Use it and use it well. Keep in mind that this device sparks when changing selections, and it sparks a lot. Sparks can create fires if there are flammable gases around.

===Analyzer / BreathDeep Catridge===
Where the RPD is your sword, the Analyzer is your eye. Use this in identifying various gases in various pipelines (more on pipelines later), in analyzing the air around you, in identifying problems, harmful gases, and other various atmospheric related occurances. This is slightly less related to the job, but the Analyzer also has a barometric function; giving you information on incoming storms when Alt-Clicked on planetary environments.

===ATMOS Resin===
The Backpack Firefighter Tank can switch modes to launch transparent ATMOS resin instead of extinguisher. This resin has the following effects:

  * Repairs hull breaches similarly to Metal Foam.
  * Cleans the air from toxins.
  * Normalises air temperature to room temperature (20°C or 293.15K).
  * Seals open vents (as if they were welded shut).
  * Removes slipperiness from floors (from water etc).
  * The foam itself is not slippery.
To use the Backpack Firefighter Tank, equip it on your backpack slot and click the new HUD icon to take out the nozzle. You can then cycle modes between extinguisher, resin launcher and single tile resin launcher (foamer) by activating the nozzle in your hand. It spends water when used. Examine the nozzle to see water remaining. This anti-breach and firefighting tool can be ordered from cargo or found in atmospheric lockers.

===ATMOS Holofan===
The holofan is a wonderful tool that can project up to 6 holographic barriers which block gas movement. You can use these holofans to isolate breaches, prevent a spill from getting worse, or even to do basic retooling of the atmospheric layout (such as using a holofan on a pressurized plasma pipe you are about to unwrench). Keep in mind however, that holofans does not block the superconduction (explained later) of hot gases and are less reliable in very high temperature environments, especially when fire is involved.

====Atmospherics Layout====

A wise Atmos Tech once said: "just stare at the pipes until you get it."

Atmospherics is pretty simple, but the pipe layout makes it slightly confusing for the untrained eye. There are 4 major pipe "loops":

The dark blue pipe loop is the distribution loop. It sends air to all the vents on the station for the crew to breathe.

The cyan air mix pipe loop, which is specialized to mix and provide the air mix to the distribution loop, and is used to fill air pumps outside the front door of Atmospherics.

The red/green pipe loop, which retrieves the gas in the station via the air scrubbers (red loop) and passes them through a set of filters (green loop).

The yellow pipe loop, internal to Atmospherics, which is used for custom gas mixes that can be fed into the canister charging station in the middle of atmospherics, or fed into the mixing tank.

In some configurations, the gas tanks of the station's atmospherics network, unlike in the rest of the station, are ordinary rooms filled with very high pressure of the appropriate gas. The output of these rooms are controlled by their respective Supply Control Computer, an on/off valve, and an output pump for each loop. Note that these rooms can be depleted, especially if someone makes a hole in a tank's external wall.

To understand how the breatheable air mix is mixed, try following these steps and looking at the map at the same time, it starts on the south end of Atmospherics, like so:

  * The gasses are pumped through the cyan tubes from their respective tanks (N2, O2).
  * They are mixed in the air tank (Air) to a 1/5 mix of O2 and N2.
  * The breathable gas is then pumped through the cyan loop to the north of Atmospherics.
  * And finally it's pumped into the dark blue distro loop and out to the station for everyone to breathe.

Next let's make up an example situation to see how the waste system works in action:

  * Scientist Bill messes up and fills the Toxins Lab with plasma but fortunately manages to evacuate the room safely.
  * Being an otherwise ideal situation Atmos-wise, the Toxins Lab's air scrubbers have been set to filter out all hazardous gases (they're not set by default, this has to be done through the Air Alarm manually or by asking the AI to do it) and plasma starts to get sucked through the scrubber into the waste pipes.
  * The plasma arrives to the Waste In -loop (the red pipe loop) at Atmos. It travels south through the pipes, its first stop being the N2 Filter.
  * If there was any Nitrogen in the waste gas, it would get filtered out here, and the rest of the gas continues its journey through the waste loop, same thing happening at every filter.
  * The plasma finally reaches the Plasma Filter. 
  * Here the plasma gets extracted from the waste gas and pushed into the big plasma tank-room outside the windows.
  * The plasma stays in the room until someone decides to pump it out.
  * Scientist Bill by now notices that the Toxins Lab has no plasma anymore and is able to safely continue his work. Yay!

===Setting Up Atmospherics===
It's about time we stop with the theory and throw it out the window and get down to business. The Rapid Pipe Dispenser (found in your locker) can dispense and secure infinite pipes, and your wrench can disconnect and connect pipes to each other. There is a very old stationary Pipe Dispenser that can be found in the room as well, but it's way faster to to use the RPD.

Next up is a very simple step by step guide how to set up the Atmospherics pipe system to be (nearly) as efficient as possible. Despite popular belief by your neighbors the Station Engineers (and the rest of the unwashed masses in the station), Atmospherics NEEDS TO BE SET UP TO WORK WELL. It's similar to the Supermatter Engine in a way; you could just start the emitters and it might make some power, but doing that with no setup is terrible and probably prone to blowing up. While atmos likely isn't going to blow up, without prior adjustments it's terribly slow and very easily clogged.

Note that this is only one style how to set up the pipes, there are many ways and they all have their own pros and cons!

For the love of NovusCorp, at least do this:
  * Select a Volume Pump in your RPD and replace the green circled normal pump with a volume pump(or a valve if you are using the waste loop as a large volume mix chamber), making the waste gas -system >100x more efficient. We want the waste gas sucked from the station into the waste system as soon as possible!
  * Set all red circled filters ON and set them to maximum pressure (200 L/s) so waste gases will actually be moved, if they're not already maxed out.

This is good as well:
  * Go through the N2 and O2 (besides southern wall) and set their output to 300 kPa. 4500 kPa drains all of atmos' gases way too quickly, there really isn't any reason to turn the pumps up to maximum unless you're flooding.
  * Set the pumps next to the computers at 300 kPa also, so the gases being pushed out of the gas-room get moved fast too.
  * Set the Air-computer's output to some amount over 300 kPa, the pumps automatically keep the gas throttled.
Replace the blue circled normal pump with a Volume Pump(potentially a valve here, there are risks to this, however) as well, but notice; there are risks involved and all of them are covered at the pros and cons -section below.

Pros and cons of this whole setup:
  * + Quick toxin filtering: In case of a toxin leak, waste gas will be sucked out quickly (if the area's air alarms are set to filter out all the toxins, that is, by default they are NOT filtering anything besides CO2).
  * + Quick repressurization: In case of a breach, air will be poured out with a nice pace, helping you re-pressurize the room quicker after the breach is fixed. The refill setting on the air alarm will also actually work with the added pressure in the distro pipe.
  * + Reduced pipe sabotaging: With this setup, its harder for the grifflords to fuck up pipes in the maintenance tunnels. In a room with the default 101.3 kPa atmospheric pressure, pipes with more than 303.9 kPa pressure fling the unwrencher in a random direction.
  * - Air Alarm sabotages: The station is more vulnerable for sabotage through air alarms. Someone can quite easily hack an air alarm somewhere and set the vents to push out air at maximum pressure, resulting in overpressurization.
  * - Space wind: In case of a breach, until the hole is fixed, you'll probably spend a small while fighting against the huge air current, a.k.a. "space wind", if you don't switch the vents off during the repair. This is mostly just annoying. to deal with this, find a pair of magboots.
  * - Very slow pipe manipulating: If you suddenly have to modify any of the distribution pipes around the station, you need to lower the pressure to under 303.9 kPa if you don't want to be flung around like a leaf in the space wind, which can take a long time.

One extra thing to keep in mind is the fact that the thermomachines around the station dump their heat collected from cooling gasses directly into the waste loop. Common sources are the cryo tubes in Medical and the machines in the Ordnance Lab. Waste tends to collect only a small amount of CO2 (which is filtered back into waste) to act as a buffer to absorb said heat. With this low amount of gas, it absorbs the heat VERY poorly and suddenly the station's waste line is a couple thousand degrees. Factor in any future fires that might add hot gas to the waste line, and this means the super hot waste gas coming into atmospherics for filtering are going to take forever to make it through the pumps and filters. Not good!

To fix this, you can add more CO2 to waste to act as a buffer for heat absorption, as well as setting up some sort of cooling for waste. This can be freezers or a heat exchanger array in space connected to the waste line. This is all entirely up to you how it gets cooled, but this is merely extra setup to ensure atmospherics runs well if you have the time to do it.

Done correctly, Atmosia should be pumping good air just faster than it's lost, and draining bad air away as fast as the traitors can set it on fire - or alternatively draining good air away as fast as a malf AI can siphon it. You can go kick back in the bar like a boss and wait for the inevitable minor station damage and cries of "Call the shuttle!" on the radio from folks who don't even know it ain't a big deal.

===Your Very Own Customized Mix===
To create a custom mix of gas, turn on the output of the supply control computers, open the manual valves, and turn the output of the pump to what you wish it to be. The gas will travel through the yellow pipes into the mixing chamber. The gas mix is pumped into the mixing chamber via a pump north of the yellow loop.

The mix obtained can then be pumped into the distribution and filtering loop or used to fill canisters. Remember to turn off the pump between the yellow and red pipe network or your custom mix will just go into the red waste loop.

====Atmospherics and The Station====
Over the course of the shift, various parts of the station might regrettably explode and vent out your precious, precious air. This is where you come in. Grab your nearest stack of metal or Rapid Construction Device and rush off to seal the breach. Grab adequate pressure and temperature protection if you don't already have it. If your distribution loop is ready, refilling should be absolutely easy. Rush to the air alarm in the corresponding area and fill the air by interfacing with the Air Alarms. You might expedite the process by setting the operating mode to "Refill" or even to turn off external pressure checks by manually setting each vents under "Vent Controls" to Internal and 0 kPa. Alternatively, hauling some canisters of air, a portable pump filled with air, or even deploying a few Proto-Nitrate crystals if you've made some can all help refill the air even faster.

Over the course of the shift, the environment might become cold or hot too. Common sources of coldness include space and icemoon wind rushing in, check for opened airlocks! Common sources of heat are usually gas combustion  and Pyroclastic Anomalies. To combat the temperature problems, there are many things that you could do:

  * You could utilize Space Heaters to warm the air up.
  * You could cycle the air; be it from the "Cycle" Operating Mode or from manually Panic Siphoning and setting the air to Refill.
  * You could even build a thermomachine and haul a portable pump to a location and keep cycling the air locally. This will heat up or cool down the air very quickly.
  * Your trusty ATMOS Resin Waterbackpack atmos.png will also set air to 20 degrees Celsius and might be of great use here, but keep in mind that it seals scrubbers and vents off.
  * You also have the holofan to prevent the cold from spreading further.
  * If you've made them in the Crystallizer, Healium crystals are quick and effective at correcting temperature issues. Just activate and throw em in!

You have great tools at your disposal, but also a great adversary to face. Good luck in your job as the Custodian of The Air!


=====Atmospherics 201: Gaseous Synthesis, Machinery, Further Theory, and Optimization=====
====The Gases and Their Functions====
Let's start with some theory about the gases. Below are the different gases that can be found in-game.

Quick note: The endothermic and exothermic descriptions in these gaseous reactions are measured with respect to enthalpy. Heat capacity can change, and this means that there might be cases where you have an exothermic reaction but the temperature is actually falling. Experiment!

Gaseous Export: Gas canisters can be exported through cargo in exchange for money. They are however, subject to elasticity and will give diminishing returns for each mole exported. Gases will roughly fall to half their credits per mole value per mole after 2100, one quarter after 4200, and 1/10th of their original base export price after 6300 moles. Diminishing returns are tracked individually per canister.

===O2===
Our first base gas is Oxygen. All humans, pets, and many other creatures need more than 16 kPa of oxygen in the air or internals to breathe. Any less and the creature starts to suffocate.

It is required to oxidize fires. The specifics of each fire reaction will be detailed down below.

Oxygen is an invisible gas. To detect it, use your PDA or a wall mounted Air Alarm. Oxygen canisters are marked in blue. Emergency Oxygen Tanks, filled with about 300 kPa, spawn in your emergency Internals Box. Larger Oxygen Tanks are in Emergency Lockers all across ship, which start with about 600 kPa.

Export price per mol: 0.2 credits

===N2===
Our second base gas is Nitrogen. Not particularly more heat absorbent than any other gas. However, it cannot burn at all, which may slow down fires simply by taking up space. It can reduce the heat penalty on the SM, which will keep temperatures down.

Export price per mol: 0.1 credits

===Air===
A 1:4 gasmix of O2 and N2 (20% O2, 80% N2). The station is filled with this.

Air in SC13 can be seen, strangely enough, as a 'watered down'-O2, with N2 being the water. Optimal atmospheric pressure for humans is 101.3 kPa. Due to the minimum of 16 kPa of O2, the pressure of 101.3 kPa cannot be changed too much without the situation becoming excessively lethal. Under 16 % oxygen? You start dying. Under 90 kPa due to fire from a while ago? You start dying. Be mindful of this.

Export price per mol: Depends on the exact percentage of O2 and N2.

===CO2===
The third gas available for atmosians from the start of a shift: Carbon Dioxide. What the fuck is Carbon Dioxide!? It's an invisible, heavy gas. It chokes people effectively and quickly, and if you can be bothered to set the alarms up, will result in a invisible room that kills those in it. Takes some setup and can be very, very annoying. Causes people to gasp at low levels. It is also often used to beef up the power generation of the Supermatter Crystal.

Export price per mol: 0.2 credits

===Phoron===
Our fourth and the most infamous of the base gases: Phoron, a.k.a. Toxins. Phoron is purple, toxic, and flammable. When ignited in an oxygenated room it will produce fires.

Phoron fires use oxygen and plasma to produce heat and waste gas. Energy released from phoron fires depends on the burn rate for phoron. The phoron burn rate itself depends on the composition of the air and the temperature of the burn. Optimal composition for maximum burn rate is 10x more O2 than phoron, with the air temperature exceeding the upper limit of 1643.15 Kelvins. Oxygen is burned at 0.4x the rate of phoron at temperatures above the upper limit. More oxygen (up to 1.4x the plasma burn rate) will be consumed for lower air temperatures.

The aforementioned waste gas of phoron fires are either solely tritium on oxygenated phoron fires (more detail on the tritium section below) or water vapor and CO2 on a 3 CO2 : 1 H2O ratio on non-oxygenated phoron fires.

Export price per mol: 1.5 credits

===N2O===
The final base gas available in the atmos tanks: Nitrous Oxide, a.k.a. Sleeping Agent. A white-flecked gas.

Makes you laugh at low doses and at higher ones puts you to sleep. If using this as a sleep gas mix do not forget to mix in at least 16 kPa of O2, or you will suffocate someone. This decomposes into Nitrogen and Oxygen at temperatures at or over 1400K, creating Nitrogen equal to the amount of N2O used, and half that amount in Oxygen.

Export price per mol: 1.5 credits

===Tritium===
Radioactive, flammable gas that is used in plenty of chemical reactions. Created by heating large amounts of O2 with Plasma. Emits radiation when combusted in the air, as well as pipes and canisters. Might not want to put this into any engine unless you plan to set it on fire.

Tritium is created in fires that are super saturated, i.e. fires where there are 96 more units of oxygen than plasma. One popular ratio used by many Atmosians is 97 O2 : 3 Plasma, this wont hit the super saturation threshold from the get go, but given time the oxygen input will overflow the oxygen burn rate, resulting in a net positive oxygen gain in the chamber and eventually hitting the threshold. This oxygen accumulation continues over time, and therefore it is a good idea to lower the oxygen ratio in the burn mix over time. Another popular mix for chambers that have burned for quite some time is 85 O2 : 15 Plasma.

Important to remember is that tritium will likely be very hot when exiting the chamber, opening possibilites of cracked canisters and eventually toasted incinerators. Prepare accordingly! It is also worthy to note that tritium when allowed to react with oxygen will burn up into water vapor. Due to the chamber having a lot of oxygen, it is often a good idea to add a second scrubber to prevent too much tritium from being lost. Keep this in mind when attempting to get sizable amounts of it.

Tritium burns in a unique fashion. There are two ways tritium can burn, a very energetic high reaction rate burn and a slower one. The former is a key component to bomb making due to the insane pressure hop on the burn tick. The high burn rate occurs when there are more oxygen than tritium in a given mix AND if the total energy of the turf is above 2 million joules. If these requirements aren't met the burn reaction will revert to the slower one which won't be as theatrical as the first one.

Export price per mol: 2.5 credits

===Water Vapor===
Pure H2O. Keep away from the Clown - this slips people and even freezes tiles when released at low temperatures.

The Janitor starts with a tank in his closet; created as a waste product on tritium fires and unsaturated plasma fires.

Export price per mol: 0.5 credits

===H2===
Hydrogen is a flammable gas which when ignited burns similarly to tritium. It is also an integral part of fusion reactions. Hydrogen is made by electrolyzing Water Vapor with an electrolyzer machine. In starships, the particle scoop can commonly harvest H2 from gas giants.

Hydrogen is solidified in the Crystallizer with BZ as catalyst at high heat and pressure (around or above 10,000K) to produce metal hydrogen sheets, which can be used to make Elder Atmosian armor, a metal hydrogen fireaxe, and golems.

Export price per mol: 1 credits

===BZ===
BZ gas is a potent hallucinogenic that also puts slimes into stasis and degenerates changeling chemicals. As a side effect, affected people will take low brain damage. BZ sees frequent use as an ingredient/catalyst in many gas reactions.

BZ is formed in an exothermic reaction when at least ten moles of each N2O and Plasma are combined at low pressures. The optimal pressure for this is 0.1 atmosphere, or about 10 kPa. Efficiency might be higher if you get it even lower somehow, though. Plasma is consumed at 2x the rate of N2O.

If mixed in a tank with oxygen, it can be used for internals, to encourage spiritual development. Breathing it also produces BZ Metabolites.

Export price per mol: 1.5 credits

===Pluoxium===
A non-reactive Oxygen substitute that delivers eight times as much O2 to the bloodstream, with as little 3 kPa minimum pressure required for internals!

Pluoxium may be created by exposing O2, CO2 and Tritium together in an exothermic reaction between 50 K and 273 K. This reaction creates a minimal amount of H2 (1% of Pluoxium created) as a byproduct. The consumption ratio for this reaction is 100 O2 : 50 CO2 : 1 Tritium.

Export price per mol: 2.5 credits

===Miasma===
Miasma (bad air) is created from bloomed Corpse Flowers and decomposing corpses. Miasma smells bad and can cause diseases to spontaneously appear. The higher concentration of miasma in the air, the higher level symptoms can appear. Sterilized into oxygen in a slightly exothermic reaction at 170 degrees Celsius. Presence of water vapor in quantities higher than 0.1 moles prevents this from happening. This reaction has the lowest priority out of all reaction in the game. It is otherwise absolutely inert in terms of atmos reactions.

Export price per mol: 1 credits

===Nitrium===
Nitrium is a gaseous stimulant that when inhaled can enhance speed and endurance. At low concentrations Nitrium will increase your top running speed while healthy and unimpaired. At slightly higher concentrations breathing Nitrium will form Nitrosyl plasmide in the bloodstream, providing immunity to stuns and sleeps. This is in addition to the speed boost. Damage slowdown from stamina damage (stun batons!) will still slow you even with the stun immunity. At high concentrations breathing it will damage a person's lungs.

Nitrium is made by combining a minimum of 20 moles Tritium, 10 moles Nitrogen and 5 moles BZ in a (slightly) endothermic reaction above 1500K. The consumption ratio for the reaction is 20 N2 : 20 Trit : 1 BZ. Higher heat improves the rate of reaction. Also formed in high quantities by fusion.

Nitrium decomposes exothermically when in contact with Oxygen under 343.15 K, splitting into a 1:1 mix of Nitrogen and Oxygen. Meaning you will have to experiment to find a way to breathe Nitrium and not suffocate while doing so if you wish for ultimate power.

Breathing Nitrium in high concentrations will quickly cause lung failure, make sure that Nitrium makes up a minority of your tank.

Export price per mol: 6 credits

===Freon===
On temperature lower than 0°C (273.15 K) Freon will create an endothermic reaction with O2, meaning it will absorb heat from the atmosphere, down to a minimum close to 50K. Adding Proto-Nitrate will catalyse the reaction so that it may begin at temperatures up to 310 kelvin, which is above room temperature. This reaction produces CO2 and if the temperature is between 120-160K the reaction has a small chance to also produce solid sheets of hot ice.

Breathing Freon causes burn damage.

Freon is made by combining a minimum of 0.6 mol of Plasma, 0.3 mol of CO2 and 0.1 BZ, with reaction speed depending on temperature, as depicted in the graph below. The reaction is endothermic. The consumption ratio for the reaction is 6 Plasma : 3 CO2 : 1 BZ, forming 10 moles of Freon. Unless you're able to push the reaction into high temperatures, it is best to try and maintain a temperature of 800K. The energy consumed by the reaction also scales up as temperature increases, so it may be harder to maintain a high temperature than one might expect.

Export price per mol: 5 credits

===Hot Ice===
Hot ice is a solid byproduct of the cooled Freon+O2 reaction at 120-160K. Can be sold to cargo at a high price. It holds a great amount of power inside. Can be ground to produce 25 units of Hot Ice Slush.

If hit with a welder or burned the hot ice will melt, releasing the power stored inside. This releases large amounts of hot plasma into the air. (Moles of plasma released = 150 x number of sheets) and (Heat released = 20 x number of sheets + 300K).

===Hyper-Noblium===
Extremely inert, Hyper-Noblium stops other gases from reacting. (Specifically, it stops reactions when >5 moles and temp > 20 K)

Can be created when Nitrogen is combined with Tritium at extremely low temperatures (below 15 K). Reaction produces significant energy (exothermic) and BZ works to reduce the energy released, expect to have your temperature spike if you don't use BZ, the energy released is potent enough to be used for explosives! 10 mol of Nitrogen is used per mol of Hyper-noblium synthesised, and you also need at least this much to have the reaction occur. 5 mol of Tritium is the minimum required to have the reaction occur, and is the amount used when no BZ is present. However, the amount of Tritium used scales with the ratio of Tritium to BZ, all the way down to 0.005 mol used in a ratio of 1:1000 Tritium:BZ. In short: keep your BZ high and your Tritium low if you want to make a lot of this stuff!

Export price per mol: 2.5 credits

===Proto-Nitrate===
Proto-Nitrate is a highly reactive gas, but non-toxic when breathed. It is created in an exothermic reaction when Pluoxium is exposed to H2 at temperatures between 5000-10000 K. Hydrogen is consumed at around 10x the rate of Pluoxium.

  * When between temperatures of 250-300k, Proto-nitrate solidifies gaseous Plasma into bars.
  * When between temperatures of 260-280k, Proto-nitrate reacts with BZ to produce radiation, Nitrogen, Helium, and Plasma, as well as causing localized hallucinations in an exothermic reaction.
  * When between temperatures of 150-340k, Proto-nitrate reacts with tritium to produce H2 and radiation in an exothermic reaction.
  * Proto-Nitrate reacts with at least 150 moles of H2 to create more Proto-Nitrate in an endothermic reaction.

Export price per mol: 2.5 credits

===Halon===
Halon acts as a fire suppressant by removing oxygen in the air (while producing CO2) in an endothermic reaction if the air temperature is above 100 C or 373.15 K. The oxygen suppresion rate is 20 O2 : 1 Halon. It is created in a slightly exothermic reaction between CO2 and N2O in turfs with an active electrolyzer on them, below 230K, and at low pressure. 2 moles of CO2 are used and 1 mol of N2O is used.

Export price per mol: 4 credits

===Healium===
Healium (not to be confused with actual Helium) is a red gas which acts as a stronger sleeping agent than N2O, while healing burns, bruises, suffocation and toxin damage.

It is created by exposing Freon to BZ in an exothermic reaction at temperatures between 25-300 Kelvin (keep it chill). Freon is consumed at around 11x the rate of BZ; a little bit of BZ will very quickly transform all of your Freon into Healium if you're not careful.

Export price per mol: 5.5 credits

===Zauker===
Zauker is an incredibly deadly gas if inhaled. It is made by mixing Hyper-Noblium and Nitrium in an endothermic reaction at temperatures between 50000-75000 K. Nitrium is consumed at around 50x the rate of Hyper-Noblium. It is worthy to note that Hyper-Noblium stops reactions when it is present in quantities above 5 moles, prepare accordingly!

Zauker also decomposes exothermically into a 30/70 O2/N2 mix when exposed to Nitrogen.

Export price per mol: 7 credits

===Helium===
Helium is an invisible, inert gas. It has minor use within the Crystallizer to make a Crystal Cell, but otherwise is functionally useless. Sell it to cargo!

Helium is produced as a common byproduct of fusion in the Hyper-torus Fusion Reactor, or from a Proto-Nitrate/BZ reaction. It is also another common gas harvested by Particle Scoops on starships.

Export price per mol: 3.5 credits

===Anti-Noblium===
Anti-Noblium is a rare gas used in high level Crystallizer recipes and as high tier fuel for the Hyper-torus Fusion Reactor. Outside of those uses, it doesn't do all that much. It does look pretty when in the air though!

Anti-Noblium can be made within the Hyper-torus Fusion Reactor when using Hyper-Noblium as the primary fuel with either Hydrogen or Tritium as the secondary fuel. It can also be created with #Hyper-Noblium in turfs with an active electrolyzer at under 150 kelvin, with a rate of 0.5 moles of Anti-Noblium per 1 mole of Hyper-Noblium.

Export price per mol: 10 credits

====Physical Characteristics of Gases====
TL;DR Gas flows from high pressure areas, to low pressure areas. Gas uses up more room when hot, less room when cold.

Ideal gas law: PV = nRT

Where R (ideal, or universal, gas constant) = 8.31, the following are linked by this equation.

Pressure (P): Measured in kPa, kiloPascals, Pressure is lethal above 750 kPa's. A pressure in a room above 1000 kPa's necessitates internals to breathe properly.


Volume (V): Another unseen variable, Volume is how much the area/canister/tank or piped tank has space inside it. This helps dictate how much gas it can hold. Volume is essentially the 'mole divider' when converting between a canister/air pump to your tank; having a higher volume essentially makes the tank that much more efficient, proportionally, so an Extended Emergency Oxygen Tank has twice the contained air per kPa in comparison to a regular Emergency Oxygen Tank.


Item	Volume
AirTank.png Emergency Oxygen Tank	3
Extended Emergency Oxygen Tank.png Extended Emergency Oxygen Tank	6
Extended Emergency Oxygen Tank.png Double Emergency Oxygen Tank	10
OxygenTank.png Oxygen Tank (blue/red)	70
Plasma tank.png Plasma Tank	70
Atmospheric Pipe.png All pipes	70
Gaspipe.png Pipe manifold	105
Locker.png Locker	200
Coffin.png Coffin	200
Ppump.png Gas Pump (each side)	200
Vpump.png Volume Pump (each side)	200
Passpump.png Passive Gate (each side)	200
Heat exchanger.png Heat Exchanger	200
Atmos filter.png Gas Filter	200
Vent.png Vent	200
Scrub.png Scrubber	200
Manifold.png Layer Manifold	200
PortableScrubber.png Portable Scrubber	750
PortablePump.png Portable Pump	1 000
Canister.png Gas Canister	1 000
Wire 1 1.PNG Tile / turf (any area)	2 500
Pressure Tank.png Pressure Tank	2 500
Huge Scrubber.png Huge scrubber	50 000

Moles (n): Moles are the amount of particles of a gas in the air. It is moles that cause odd effects with a certain chemical. As it dumps so many moles to a tile, to keep the pressure acceptable, the moles have to be very, very cold, causing the infectious effect. Moles can be calculated by a form of the ideal gas law. n=(P*V)/(R*T)

Temperature (T): Measures in K, Kelvin, Temperature above 360 K and below 260 K causes burn damage to humans. Canisters rupture when the air surrounding them is over 1550 K.

Heat Capacity: A gasmix has heat capacity, and it is calculated by taking into account the quantity of all of the gases in the air and their specific heat. Heat capacity defines how much energy it takes to raise the temperature of a gas. The normal air mix (%30 O2, %70 N2) has a specific heat capacity of about 20 which doesn't impede heat transfer very much. Fires spreads quicker in gases with low heat capacity, and slower in gases with high heat capacity.


Gas	Specific heat capacity (molar)
O2	20
N2	20
CO2	30
N2O	40
Plasma	200
Tritium	10
Water Vapor	40
Hydrogen	15
BZ	20
Pluoxium	80
Miasma	20
Nitrium	10
Freon	600
Hypernoblium	2000
Proto-Nitrate	30
Halon	175
Healium	10
Zauker	350
Helium	15
Antinoblium	1



Fire: An effect caused by the ignition of plasma, tritium, and hydrogen in an oxygenated room. It causes massive burn damage, and raises the temperature of the room.

In short the colder the gas and the higher the container volume, the more moles you can fit inside. This is why hot gases clog the red waste pipes - they expand, allowing fewer moles to be transported.

====Breathability====
Do note that breathing is based on pressure and not moles! Moles breathed has no bearing on suffocation, only on gas consumption.

Humans need 16 kPa of O2 to survive. When not breathing through internals this 16 kPa is supplied by the environment, with a normal 21-79 mix of 101 kPa O2-N2 supplying 21 kPa of Oxygen to the lungs.

For internals this means that you are going to need a minimum of 16 kPa release pressure on the tank (adjusted by clicking the tank while in hand). Unpure mixes will require a higher release pressure to be breathable!

===Consumption===
The consumption rate for gas is dictated by the moles breathed in, all oxygen intake will be consumed and turned into carbon dioxide. Lungs are considered to be 2 Litres. Mole consumption works as follows:

  * For most scenarios this is equal to 2/2500th of the environment gas.
  * For internals this is further modified by the release pressure of the tank, with the breathed gas targeted to reach whatever release pressure set when inside the lungs. You can calculate this by using n = Release Pressure * 2 Litres / (8.31 * Temperature). A higher temperature will mean less gas will be breathed in per tick. This does not mean a longer internal, since the ratio of gas breathed in to the total gas in tank is still the same.

===Temperature===
Creatures start taking damage when the air breathed in is colder than 260 Kelvins or hotter than 360 Kelvins! This is separate from the cold or hot damage taken because a mob is too cold or hot though. There are damage increases in temperatures colder than 200 and 120 Kelvins or temperatures hotter than 400 and 1000 Kelvins. This damage is further multiplied for species such as lizards who take 3/2 times as much cold damage but 2/3rd as much hot damage.

===Notes on optimization===
Pluoxium is considered to be 8 times as potent as Oxygen for breathing I.E. each kPa of pluoxium counts as 8 kPa. It's possible to run a pluoxium tank with release pressure as low as 2 kPa for a longer lasting internal.
If external efficiency is important, it's possible for a hotter internal mixture to be made to conserve the amount of moles while still supplying an equal amount of partial pressure to the lungs.

====Thermomachines====
Combined entity of freezer and heaters, thermomachines allow you to influence the temperatures of gases connected to it. Thermomachines heat or cool the gas in their port to the target temperature.

An ideal thermomachine working at full efficiency "combines" the gas mixture actually present inside it with a gas mixture of a set temperature (depending on the user input) and heat capacity (depending on the quality of matter bins present). A heater will always work under the aforementioned ideal circumstances, while a cooler can get throttled down to a minimum of 65% efficiency.

Thermomachines need to have gas present inside it to properly cool or heat.

====Fusion====
For a much more in-depth look to the Hypertorus Fusion Reactor, see Guide to the Hypertorus Fusion Reactor.

So you want to operate a fusion reactor? Well, it's about as dangerous as it sounds. On /tg/station, fusion has been redesigned several times and is currently on version 7: "Hypertorus Fusion Reactor (HFR)"-edition.

In version 7 of fusion, you must build a machine called Hypertorus Fusion Reactor. The HFR is a 3x3 multi machine that needs the proper setup to be built. In most maps you'll find a proper space with outlines on the floor to designate where to put each piece.

First thing first, you need to build the core of the machine. This piece has ONE port that is used for cooling the internal fusion mix, you can rotate the machine simply by using a screwdriver and a wrench (similar to how you rotate a freezer/heater).

After the core is done, build the 4 corner pieces in the corners of the grid and the 4 ports for fuel, moderator gases, waste and interface. 

Once this is complete, finalize it by hitting the interface with a multitool.

A little piece of paper will show up, it contains tips on how to operate the machine that you won't find here, so read it carefully!

Now that you know how to build it, let's see what all those buttons do by starting from opening the interface.


HFR Interface top.PNGHFR Interface bottom.PNG

Click expand to see how to operate the HFR Interface.

The interface it’s quite big and it has an overwhelming amount of informations but we’ll go through them one by one (you can also scroll to access all infos)

HFR i switches.PNG
Those are the main controls, they control how the machine will behave
-Start Power starts the machine main loop and allow power drain and activates the other controls
-Start cooling starts the machine cooling loop, the one connected to the core
-Start fuel injection starts the fuel injection in the machine which will start the main fusion loop and thus starting the reaction itself
HFR i gasmixes.PNG
This will contain the gas mixture of the fusion gases and the moderator gases

HFR i parameters.PNG
Those are the main parameters of the fusion reactor
-Power level goes from 0 to 600, from it depends the amount of power consumption (from 50 KW at PW 0 to 350 KW (it will be higher in the future)), the volume of the noise the machine makes, the damage the machine will take, the ability to turn off the machine safely (at high power level you can’t), fuel consumption, various other gas reaction/interactions.
-Integrity indicates the integrity of the magnetic containment field inside the machine, if it reaches 0 the machine will explode, is controlled by how many moles of gas are inside the fusion gasmix and their temperature and by other factors.
-Iron content is the amount of iron being produced inside the reactor, at high amounts will actively lower the integrity by damaging the fields, can be lowered by lowering the fusion temperature.
-Energy levels depends on the amount of moles inside, the kind of gas inside and the moderators too will have different impact.
-Heat limiter modifier will change depending on the power level, will limit the amount of heat the fusion can increase/decrease each tick (hotter gases are easier to heat up/cool down)
-Heat output is the main parameter affecting the temperature of the fusion reaction, is limited by the Heat limiter modifier and is affected by many other factors.
HFR i temperatures.PNG
Those will show the gases temperature in real time
The flow of heat is Fusion > Moderator > coolant
(output gas will have either moderator or fusion temperature depending on the source)
If you don’t add a moderator the heat will go directly from the fusion to the coolant, but is much more inefficient.
HFR i inputs.PNG
Those are inputs that the user can change
-Heating Conductor will change the Heat limiter modifier, higher numbers means higher heat transfer. The Heat limiter modifier will affect the Heat Output by increasing/decreasing the maximum range possible; keep it at 100 for normal operations.
-Magnetic Constrictor will actively change the volume inside the fusion reactor, this affect instability and power output. Increasing the number will increase the volume available to the fusion gases, allows higher instability fluctuations and increases the influence of every gas inside the machine (positive and negative influences). Keep at 100 for normal operations.
-Fuel and moderator injection rate will change how much gas will enter the machine this affect consumption, and other gas related interactions
-Current Damper, life saver, will actively increase the instability of the fusion reaction making the reaction endothermic, that can set the heat output to negative cooling down the fusion mix, useful in meltdown situations. Counteracted by iron content.
-Waste remove will start to output helium/antinoblium at a fixed rate from the fusion mix and the gas you set to filter from the moderator mix allowing the user to filter out specific gases from the moderators

And now let's learn what each gases will do inside the machine
Click expand to see the HFR gas interaction section.

First thing to learn is the fuel: only a mixture of Tritium and Hydrogen will enter the fuel input port, no other gases will go inside (at least for now)

The moderator gases are special gases that have a double function, first they allow proper cooling for the core, second they have interactions with the functioning of the fusion reaction itself, those interactions are:
-for the fusion gasmix:
--Hydrogen = increase the energy of the system and increase the heat modifier
--Tritium = increase the energy of the system and increase the power modifier
--Helium = decrease the energy of the system, increase the heat modifier and increase the radiation modifier
-for the moderator gasmix:
--Nitrogen = increase the energy of the system, decrease the heat modifier and decrease the radiation modifier
--CO2 = increase the energy of the system and increase the power modifier
--N2O = increase the energy of the system and decrease the heat modifier
--Zauker = increase the energy of the system and increase the power modifier
--Antinoblium = vastly increase the energy of the system and vastly increase the radiation modifier
--Hypernoblium = vastly decrease the energy of the system
--H2O = decrease the energy of the system
--NO2 = decrease the energy of the system and increase the power of the system
--Healium = decrease the energy of the system
--Freon = decrease the energy of the system, decrease the power modifier, decrease the heat modifier and decrease the radiation modifier
--Oxygen = decrease the power modifier
--Plasma = increase the power modifier, increase the heat modifier and increase the radiation modifier
Now you know how to build and operate the HFR - Hypertorus fusion reactor! Many other informations and tips are provided in game in the proper pamphlet after activating the machine, enjoy!

Now you know how to build and operate the HFR - Hypertorus fusion reactor! Many other informations and tips are provided in game in the proper pamphlet after activating the machine, enjoy!

====Crystallizer====
The Crystallizer is a machine that allows gases to be solidified and made into various materials.

The working principle and gaseous requirements behind the crystallizer is rather simple and explained in the machine itself. You select a recipe, pump gases in using the input (green) port, meet the temperature requirements, and wait for the material to finish crafting. The red port is used for heat control, as it will conduct with the internal mix and influence the temperature. You have a 10% wiggle room for the temperature requirements, but straying too far from the optimal temperature will influence the final quality of the item produced. Quality affects the amount of gas consumed for each product produced, with higher qualities consuming less gas. The optimal temperature for any given recipe is the median between the lower and upper temperature bound. Stay as close as you can to the median value, and you'll be able to save up to 85% of the required gas if you manage to make the highest quality!

It currently supports the production of:

  * Metallic Hydrogen: A crafting material used for golems, axes, or the Elder Atmosian armor set.
  * Hyper-Noblium Crystal: A two use potion that can be used to pressure-proof two clothing items, turning them an icy blue color.
  * Healium Crystal: A grenade that can fix a large are of air to more reasonable temperatures. Good for firefighting and freezing temperatures.
  * Proto-Nitrate Crystal: A grenade that can refill a room with nitrogen and oxygen with a 8:3 split respectively.
  * Nitrous Oxide Crystal: A grenade that will release Nitrous Oxide (Laughing Gas).
  * Hot Ice: A material normally prodouced by freon combustion, also craftable with the Crystallizer. When weldered or burnt, it rapidly releases a very hot and dense cloud of plasma gas.
  * Ammonia Crystal	A material with not much use except for exporting. Makes 2 every time it's completed.
  * Supermatter Shard	A smaller version of the extremely dangerous Supermatter Crystal used for power generation.
  * Diamond: A sheet of diamond. Many crafting and manufacturing applications. Used thorough the station.
  * Plasma Sheet: A sheet of plasma. Many crafting, manufacturing, and biological applications. Used thorough the station.
  * Crystal Cell: A non rechargeable cell with a huge power capacity. Rated at 50 MJ.
  * Zaukerite: A material without much use except for bragging rights. Makes 2 every time it's completed.
  * Drone Fuel Pellets: Three separate recipes that create Fuel cells used for drone explorations in Cargo. Comes in three qualities denoting the difficulty of gases used.
  * Crystal Foam Grenade: A grenade that functions exactly like the standard Smart Metal Foam grenades that can be found roundstart. Extremely simple to make compared to most other recipes.
  * Nitrium Crystal: A grenade that on detonation releases a chemical smoke cloud containing chemical Nitrium and Nitrosyl Plasmide.

====Bluespace Gas Vendor Hub====
This is the hub for gas purchase done by the crew. You only need to pipe your gas in and it will distribute it across vendors available station-wide. You can also set a price per mole for the gases. The gas will be at 20 degrees Celsius and is capped at 1013 kPa when purchased by the crew, so do keep this in mind. You can also refill the individual vendors with metal for it to make more tanks.

====After the Work is Done====
This is a section dedicated to various tips and tricks, trivia, and things that you could do in your spare time:

  * First and by far most important: make sure pipes don't get broken and if they do, fix them.
  * Go around swiping your ID on Air Alarms, setting the operating mode to contaminated, and then re-swiping to lock it. You can ask the AI to do this as well, and probably should.
  * Fill all the air pumps with air using a volume pump, these work until 9000 kPa compared to the pressure pump's 4500.
  * Go to the red lockers, get a hard hat, gas mask and everything else that might be of use. Remember that you need both a fire suit and a hard hat to be resistant to weak fires. One will be useless without the other.
  * Go grab the Fire Axe from the wall mount and hide it somewhere so the chucklefucks won't get it and go killing. DON'T take it with you and go walking through the hallways trying to look like a badass, you'll be the prime target of any antagonist/griffon who needs an efficient weapon.
  * Least importantly, maintain the disposals system. You can generate pipes, but it needs welding and is generally a pain in the ass. You can also make fun slides, though.
  * Using H/E pipes in space you can cool things down to a very low temperature very quickly. By making a cross with two off them you can have two on.
  * Gas pumps are for precise pressure control, volumetric pumps are for really fast pumping, and passive gates are for having 'one way' manual valves.
  * Extremely high-temperature gases (like those from a panic siphoned fire) can really clog the waste loop. Could you do something to correct that?
  * No one uses the ports outside of the 'refilling' station, but that doesn't mean that functionality can't be added onto them!
  * The wall section that looks like the letter 'I' can be dismantled if you need more working space for pipes.
  * Don't count out the grated window areas, they can be a great (har har) way to utilize the vacuum of space without an EVA suit.
  * Speaking of EVA suits, your engineering buddies can potentially help you with anything you might want to do in space, be it adding or modifying pipes. Watch the hilarity as that incompetent engineer fumbles when setting up a heat exchanger pipe loop!
  * The mining station doesn't have air recycling. Very long rounds might make this a problem for any miners working there.
  * Any gas at pressure over 1000 kPa will cause you to start suffocating as in a vacuum. You can just use internals, though.
  * N2O is invisible at low pressures. If you start giggling, put on your internals to avoid passing out.
  * Any gas can displace O2, and less than 16 (also useful for optimizing internals) kPa of oxygen starts the Oxyloss. CO2 can be removed with the scrubbers, but to get rid of N2 simply apply some way of removing gas from the air and adding O2. My personal favorite is 2 air pumps, 3 connectors and an Air Filter and a canister: 1 pump draws in, goes through the connection and filters N2 into the canister, and the rest to the other pump, which expels it. Can also be used for N2O which is only sluggishly scrubbed otherwise.
  * Pressures above 750 kPa do 10 DPS + 5 DPS for every extra 375 kPa above that mark, rounded off. Space suits completely block it all, but there is no other defense.
=====Atmospherics 301: Pipeline and Pipenet Theory; LINDA: Active Turfs & Excited Groups; Superconduction=====
LINDA? What is LINDA? LINDA is our atmospherics system. There are various theories on the origin of this name, but that is not why we are here. We are here to understand how gas dissipate, how pipelines and eventually pipenets are formed, and the more technical parts of atmospherics.

For a technical and detailed breakdown of our atmospherics subsystem and how everything works, refer to https://github.com/tgstation/tgstation/blob/master/code/modules/atmospherics/Atmospherics.md

This will be an abridged version of that guide, intended for those without any experience in codediving. This not a substitute for that guide however, and we highly implore you to visit the documentation, even if you don't have any experience in reading code-heavy documentations.

We will use the supermatter and various figures as scenarios; this guide is best read once you know the basics of how supermatter works and have read the guide.

====Pipeline and Pipenet Theory====
If there is one part of Atmospherics 301 that you should read, this is it.

Our atmospherics subsystem does not simulate flow. Every interlinked pipe is connected into a single pipeline, and every pipeline member is subject to gas sharing. That is to say that when you use your Analyzer on a single pipe, what you are seeing is the gas mixture of the pipeline (this returned gas mixture information doesn't include gas inside of machineries like pumps, only the regular pipes, but they are considered as extra member of the pipeline and are subject to the same gas sharing rules.)

(Extra note: in the code, we store gas information for each calculated atmospheric entity in datums called gas mixtures, this is important terminology right here, but you don't need to worry too much about this.)

Each pipeline has a gas mixture, each individual member of the pipeline gets a share of this big gas mixture based on how much their share of the total volume is. Lets take the picture on figure 3.2 as an example. Notice that the pressure is preserved on all the analyzed machineries, demonstrating that once again: the gas is being shared equally between all of them based on their respective volume. This is what the supermatter guide refers to as gas directly appearing in the two ends of the pipeline as wide as the observable universe. Keep this concept of gas sharing in mind!

Most atmospheric devices perform actions only on the gas directly under their influence; the gas that are directly present in their system. You can take a look back at the volume pump in figure 3.2, the volume pump will only move the gas directly inside their gas mixture. This is why taking gas out of the huge distribution loop is tedious and long, this is why some supermatter setups will lack moles directly inside the chamber if you expand the cooling space loop too much, this is why thermomachines are less reliable on very huge pipe networks.

Layer manifolds and valves connect different pipelines together by doing gas redistribution. Pumps however, does not. They have two gas mixtures that when connected, will be part of two separate pipelines. These pipelines will not interact with one another, but the gas will be allowed to move in one direction when the pump is turned on. You can imagine these with cups of water and salt being mixed in various forms and being put sideways; valves and manifolds combine both the cups by gluing it, while pumps work by adding a filter paper and only allowing water to flow into the salt cup and not in the reverse direction. This is why the supermatter guide goes into length on removing pumps, because they are only there to restrict flow and create pressure gradients, not to mention how they are prone to clogging.

We go into great lengths in explaining pipelines and pipenets because it is very important and will show up again and again in your journey as an atmospheric technician. Now buckle up for a shorter exposition of environmental atmospherics!

====LINDA: Active Turfs and Excited Groups====
Our atmospherics system: LINDA, work based of concepts of active turfs and excited groups. A turf (tile) will become active when any gas changes happen, be it a plasma canister being opened, a breach occuring, or as simple as scrubber taking CO2 out. A turf will also become activated if a wall is deconstructed, necessitating it to be filled. These active turfs will combine into an excited group and equalize every several iteration of the subsystem ticking. This is LINDA in it's simplest, most abridged form.

====Superconduction====
On high temperatures (above 100 degrees Celcius), superconduction occurs. Superconduction allows heat to transfer between closed turfs, it is what allows glass to break on plasma fires, and why windows are really bad insulators. In short, superconduction is the interface between the turf and the gas mixtures. You will not need to understand the inner workings of this phenomenon during your course as a technician, but keep in mind its effects.

Another very visible effect of superconduction is on super hot turf based fires (incinerator springs to mind). Reinforced floors have the temperature of 20 degrees Celsius and a very very high heat capacity. This means that these reinforced floors will almost always never move their temperature and stay at 20 degrees. Very hot gas mixtures on top of reinforced floors will constantly try to share heat with the floor and lose energy. In other words, reinforced floors constantly cool your fires down. This makes reaching very high temperatures on turfs very difficult.

It is possible to try and circumvent this phenomenon by burning things inside a canister or pipes.

Stimulum.pngBeing a Traitorous Scum
Or: How to get the AI lynched; How to call the shuttle as Atmos Tech, step-by-step:

Open valves connected to harmful gas you want to add to the station.
Set pumps to the distribution loop to maximum pressure output (4500 kPa).
Set filters to not filter harmful gasses you want to add to the station OR set the waste-in pump to 0 kPa (but leave it on to confuse the crew).
Open valve from custom mix chamber.
Turn on pump leading to distribution loop.
Wait for vents to slowly kick out your deathgas mix as regular atmos drains out through the inevitable hull breaches (alternatively turn off pressure checks on air alarms' vents to speed things up).
If you need to kill someone for your objective, and you want to be more proactive, the Fire Axe mounted in the wall is surprisingly effective. Just don't leave it lying around, because it's one of only two on the station.

To hurry this process up, you can set the air vents at local control panels to maximum output pressure. Not doing so gives the AI and Atmos Techs more time to notice what you've done and shut it off before it takes effect.


A faster process for achieving the same result is to do the following:

Disconnect, change the direction of, and reconnect the pump that feeds from the air mix to the mix tank in the north-eastern room of atmosia.
Open the valves for your deathgas mixture of choice.
Power on and max the pressure on every pump in the mix pipes (yellow pipes) from the storage tanks out to the station output (blue pipes).

This simply means that instead of the air mix being put into the mix tank as it normally does, the air mix (which may or may not contain death gasses) is fed into the station output.


Crafty atmos traitors will want to cut cameras, replace pumps with pipes, use tricky pipe configurations to avoid the AI interfering or the detective trying to fix it and make a hole in the station's oxygen and air tanks, venting the entire round's supply of oxygen into space.


An extremely fast method that involves a clever use of the waste system is the following:

Reconfigure the piping to connect the waste system directly into the pure pipes.
Find a place with a waste pipe next to a distro pipe, then configure them so that they can be united later.
Open the valves for your deathgas mixture of choice, the waste piping should now begin to fill with your gases.
Set as many air alarms as you can to have every vent at Internal 0.
When ready, go back to your distro/waste pipe spot and unite them.
Listen to screams over the radio.

Your powers don't extend to just fucking with the station's air. High level gas synthesis is a valid option and can grant you some crafty gasses and items to aid you in devious acts:

Nitrium is immediately the most obvious choice for brute force combat scenarios. Speed is incredibly strong and rare to see outside a few sources like chemistry or genetics. It also prevents you from sleeping so it can be combined with Healium for passive healing.
Healium has a strong healing effect but quickly puts you to sleep if you're breathing it. Perhaps you can find a way to stay awake while breathing it. Or you could use it as a stronger N2O to gas crowds of people with. It also sells at Cargo really well for how relatively simple it is to make, if you want to make use of what Cargo has to offer.
Tritium is notorious for creating roaring fires and can quickly send the crew into a panic if spread in large quantities. It doesn't take a genius to figure out where large amounts of tritium come from though, so expect unhappy visitors in atmospherics.
Water Vapor, a side product from tritium fires, can be collected in canisters to unleash in the halls as a sort of water bomb to make everything slippery. Consider an investment into no-slip shoes.
Freon can make things very chilly very fast, and combined with Water Vapor can create super slippery frozen tiles that send those who slip flying down the hall.
Pluoxium isn't incredibly useful for traitorous activities, but a full tank of it can let you camp out in space for a VERY long time if needed.
Zauker is... well, pretty bad for gassing places since it just turns into air when it comes into contact with nitrogen. However, a dedicated sealed chamber of it could be incredibly lethal for anyone stuck inside. Another idea is replacing the emergency tanks around the station with ones filled with pure Zauker, so that the next unfortunate soul who needs air gets nigh instantly killed upon turning on their internals. Consider sneaking these into people's pockets...
Hot Ice can be best described as pocket sized plasmafires. Much easier to target specific areas compared to plasmaflooding distro or dragging a big obvious canister of the stuff in. Ignite in hand while wearing your firesuit and drag any victims in to your new hellfire.
N2O crystals can be configured like grenades to detonate instantly like other grenades. Meaning, you could just walk up to someone and almost instantly put them to sleep by detonating N2O in their face, assuming they aren't using their internals.
Hyper-Noblium crystals can pressure proof your gear, allowing immunity to pressure hazards and removes the need for a hardsuit to spacewalk. Increasing survivability and mobility is always a plus.
Metallic Hydrogen and it's products are somewhat underwhelming but not to be forgotten. Elder Atmosian armor isn't great compared to some other options, but it does protect the limbs unlike a normal armor vest which is something to note. Metallic Hydrogen fireaxes are identical to normal fireaxes in function except for doing exactly one (1) less brute damage. Why? Fuck you, that's why. With 20 bars of your hard earned metallic hydrogen you can create a golem shell to make your own minions. Metal Hydrogen golems are immune to magic, flashes, heat and fire, but lose the cold and space immunity that all the other golems have. You'll never match xenobiology in the amount of golems you can create, but it's a nice option to have a golem bro help you in your deeds.

Other antagonistic things to do:

You can hack an air alarm to use it as a non-Atmos Tech.
You can remove the digital valves to shut down AI control, or disable the cameras if you know there are no Cyborgs on the station.
Using a gas filter turned on to pour large, ever increasing, amounts of gas onto a single connector port has no visible effects, but if you wrench a canister onto it then the canister will almost immediately fill up with the massive pressure buildup, letting you get super-high pressure plasma/CO2/etc canisters to hit area's with.
You can make a powerful single-tank bomb assembly gas mix by pumping in 2553kPa of plasma heated to 698.15 Kelvin into an empty handheld oxygen tank (not the small emergency ones).
------
Atmospherics: The Department

Your department. Click to bring up a larger version.

Contents
1	Atmospherics: The Department
1.1	What Do These Colors Mean?
2	Principles and Concepts
2.1	Pressure
2.1.1	Delta P
2.2	Temperature
2.2.1	Molar Heat Capacity
2.3	Volume
2.4	Moles
2.5	Math
2.6	Simulated vs Unsimulated Turf
2.7	ZAS
3	Gas Gas Gas
4	Relevant Tools
5	Pipes and Devices
5.1	Basic Pipes
5.2	Devices and Utilities
5.2.1	Non-Pipe
5.2.2	Unary
5.2.3	Binary
5.2.4	Ternary/Quaternary
5.3	Portables
5.3.1	Handhelds
5.4	Unimplemented
6	Air Alarm Operation
6.1	Basic Interface
6.2	Scrubber Control
6.3	Vent Control
6.4	Environmental Modes
6.5	Sensor Settings
Welcome to Atmospherics, the place where Dreams Come True™. Or at least the place that can partially sustain the ability to dream... y'know, by allowing you to breathe and stuff. Breathing is important, and the primary function of this maze of pipes and gas is to distribute breathable air throughout the ship efficiently, and to restore air to depressurized - but hopefully air-tight - rooms. Its secondary function is to process contaminant gases captured by the scrubber network and sort the gas accordingly into one of many chambers.

If you're new to all of this - or even just someone who's never really given Atmos a fair shake - then this will all look very complex and downright intimidating to look at. This mostly stems from just how much stuff can get on screen at once, but there's a few things put in place to make pipe-readability easier on the user if they just take the time to truly examine what each pipe network is meant to do. Alongside that will be this guide to help you out. You are by no means required to read all of this to start messing around with pipes, or even to join as an Atmos Tech. The goal of this guide is to elaborate on how every device works, allowing you to use this as a reference to determine what pipe does what and what pipe might be best to use in your setup.

What Do These Colors Mean?
So there's a lot of pipes with a bunch of colors and they all look really important. It's true that all of the colored pipes - which represent different pipe networks - have their place in the department, but not all of them are strictly necessary to produce gas. Here's all of the important colors, though note that some colors are the same as the chamber they correlate to:

Air Mix: The dark blue pipes near the N2, O2, and Air chambers represent the air mix loop, and these pipes are the most important: they're the ones that contain the air mix, which is combined at a mixer set to specific percentages to ensure that the gas everyone breathes is, in fact, breathable. Tampering with the mixer is ill-advised, as is modifying this network in such a way that it will not be able to reach the distribution network.
Distribution: Equally important is this blue network, which begins south of the four main chambers in atmos and is spread across the entire ship, and is its own type of pipe. This massive network of pipes is what will actually distribute the air that it receives from the air mix loop and send it all towards vents placed all around the Horizon, ensuring every room remains at optimal pressure.
Scrubber: This red pipe comes in from the west side of atmos, and is its own type of pipe. These pipes are part of the scrubber network and, as you can imagine, much of this network is comprised of scrubbers. The end of this line - where all of the scrubber pipe contents are pumped out towards - is the filtering line.
Filtering: These pipes are part of the filtering network, a pipe line connected to the scrubber network that leads to filtering devices which will filter a select gas out of the line and output it into a large storage chamber full of that same gas. If the gas type does not match then it'll continue down the line until it eventually does reach where it's meant to go. If, somehow, it reaches the end of the line and doesn't match any of the filtering criteria then it will just be output into the mix loop.
Mix: This line is a bit odd, but its intended function is to provide a pipe network that you can pump any of the gases in atmos into, allowing you to make custom mixes and letting you warm them up or cool them down. Using this line isn't necessary for Atmos to function, but it's good to use as a test bed of sorts if you'd like to experiment with how devices interact with pipe networks. Note that part of this network is colorless.
Principles and Concepts
Gas is surprisingly complex, and it should be in a game that's been dedicated to gas simulations since its inception. On the surface level it doesn't really seem like there's a lot going for it; the ship is filled with air, sometimes that air disappears, and there's crazy numbers on the wacky gas canisters that hold stuff. Here we'll describe what makes gas, gas, so that you know exactly what you're breathing!

Pressure
Pressure, put simply and in the context of atmos, is the amount of force exerted by a gas on its surroundings/container: a canister, an oxygen tank, a hallway... these are all containers. More commonly, pipes are usually what will contain and distribute gas throughout the ship. High pressure gas inside a container that is allowed access to another container at a lower pressure - no matter how significant - will always try to balance itself across the two containers and make them both equal.

There are a number of things that go into calculating pressure, but for the most part, every programmed gas is considered an "ideal gas" (the molecules that make up the gas do not interact with each other), therefore 200 moles of Phoron will pressurize a canister to the same level as 200 moles of any other gas at the same temperature. Just because a large room maintains an air pressure of 1 atm doesn't mean it has less gas than a canister with 3 atm of air. On the contrary, depending on the size of the room and the canister, the room can have significantly more gas molecules than the canister.

Almost everything that takes readings of gas will measure it in Kilopascals (kPa), or one thousand Newtons of force exerted upon one square meter. Another potential unit of measurement will be the Standard Atmosphere (atm), which is 101.325 kPa. One Atmosphere represents the standard pressure of Earth's air pressure at sea level, and is the pressure that all vents connected to the distro loop will try to maintain by default. 2 atm will be roughly 202 kPa, for example.

Fun fact: though not simulated in SS13, lower pressures reduce the boiling point for a lot of matter. Water can boil if exposed to an atmosphere of 10 kPa or lower while only sitting at room temperature. Blood can also boil this way. Don't get exposed to vacuum in real life!

Delta P
Delta P (ΔP), also known as the difference in pressure, is something one should always be aware of when dealing with hard vacuum and/or high pressures. Delta P can be dangerous in situations both big and small, namely when attempting to access a room at a much lower pressure than the one you are accessing it from, and attempting to modify pipes containing high pressure gas respectively. As mentioned above, a gas that is allowed access to a medium at a lower pressure will always try to balance itself across the two mediums, but what wasn't mentioned is how violent this can get: two rooms with an open door and very little pressure difference will suffer a small breeze at worst, but opening a door to space in a pressurized environment can be downright explosive, that is to say, you will almost definitely get ejected into space at a very high speed. If you're lucky then you'll be knocked over at a minimum, and maybe slam into a wall or two.

This same principle applies to pipes as well, in a way. While airlocks have powerful motors that can force themselves open during pretty much any circumstance as long as they're allowed to open and powered, you do not; a pipe pressurized to the extreme cannot be modified in any way, it is stuck, and the force of the pressure is too great to knock the pipe away from the rest of the network. Unless you have a pipe wrench, you won't be able to modify a pipe unless the pipe's internal pressure (the pressure of the gas inside the pipe) is brought closer to the pipe's ambient pressure (the pressure of the room around the pipe). The exact point where a pipe cannot be modified without a pipe wrench is when the difference between the pipe's pressure and its surroundings exceeds 202 kPa (2 atm). For the sake of example, a pipe pressurized to 2 atm cannot be modified if the pipe is exposed to vacuum (0 atm).

Temperature
Temperature is another important factor in determining how a gas behaves. Its most basic factor is that hotter gases will expand - or increase in pressure - while cooler gases will contract - or decrease in pressure. Remember that pressure does not equal mass; there is nothing being taken away when you heat or cool a gas, there is still a set amount of gas molecules in play. Interestingly enough, temperature's relationship with pressure is linear as long as the volume is kept constant; they're proportional to each other. You can calculate this change with Gay-Lussac's Law down below.

All temperature readings are given in either Celsius (C) or Kelvin (K). The two are easily interchangeable since Kelvin is just Celsius plus 273.15. Celsius is easy to use because its upper and lower bounds are easy to remember: 0C is the freezing point for water while 100C is the boiling point for water. Kelvin, on the other hand, is used for more precise measurements; 0K (also known as Absolute Zero) is the minimum theoretically possible temperature, that is to say, it cannot physically be reached.

Obviously a lot more comes into play with temperature: most sentient beings inhabiting the ship don't like temperatures that can boil or freeze water, and would prefer to breathe room temperature air maintained at 20 Celsius, or 293.15 Kelvin, the temperature that most atmospheric devices are set to by default. Temperatures that deviate greatly from this can have an undesirable effect on the crew.

Molar Heat Capacity
Temperature is kinda crazy, but did you know that different forms of matter heat up at different speeds when exposed to thermal energy? In our case, a room full of Phoron being heated up by an energized Supermatter crystal will take longer to reach a temperature of 5000K versus that same room and Supermatter filled with Nitrogen instead because Phoron has a specific heat value of 200 while nitrogen only has a value of 20. Conversely, Phoron heated up to 5000K will take much longer to cool down versus Nitrogen heated to the same temperature undergoing the same process.

As a real life example, compare a spoon made of aluminum versus a small glass of water, pretending that the glass itself doesn't factor into any of this besides being a storage medium and the water is the same mass as the spoon. If you held a lighter to the spoon for five minutes and touched it, you would probably burn yourself. Conversely, if you did the same thing to that glass of water, it would only feel warm by comparison. This is because H2O has a much higher molar heat capacity than something like aluminum, and is why water is often used to put simple fires out; because the energy required to heat that water up far outweighs the energy that can be produced by that fire, assuming its fuel is susceptible to getting wet.

Volume
Container	Volume
Emergency Oxygen Tank	2L
Extended Emergency Tank	6L
Double Emergency Tank	10L
Oxygen/Anesthetic Tank	70L
Jetpack	70L
Hydrogen/Phoron Tank	70L
Hydroponics Tray	100L
Portable Scrubber	750L
Portable Air Pump	1000L
Canister	1000L
Turf	2500L
Volume, put simply, is a container's capacity, more specifically just how much gas the container can hold. A container with a volume of 70L can hold more gas molecules than a container that only holds 20L. Even if the container with the smaller volume has a higher pressure, that doesn't necessarily mean it has more gas, it just means there's more force being exerted inside the smaller container. You can look into this specific relationship by using Avogadro's Law down below. Volume is always measured in Liters (L) unless it's a liquid, then it's measured in some mystery units or something. There's really not much else to explain here, but to the right is a table showing the volume of every gas container besides pipes, which can be referenced here.

Moles
The only true way to measure how much gas is actually in a container, Moles (n) will tell you how many gas molecules are in a medium. Moles, as you've hopefully learned in chemistry or physics class, is 6.022*10^23 molecular objects (Avogadro's Constant). Unless you're still stuck in biology, in which case, they're just wacky subterranean mammals to you. Unlike pressure and volume, moles are the surefire way to determine exactly how much gas is in a container since it, in itself, is unaffected by pressure, temperature, or volume.

Besides this, the molar mass of a gas only really plays into how fast a pump will operate with the gas in question. Higher molar mass means that the pump will operate slower. Does this actually matter? No, not really.

Math
Everything under this heading assumes that pressure (P) is measured in kilopascals, volume (V) in liters, moles (n) in... well, moles, and temperature (T) in Kelvin. The ideal gas constant (R) will always be 8.314 as dictated in the code.

Boyle's Law: PV=R or Pressure * Volume = 8.314, basically this law represents the relationship between pressure and volume. For example, if you were to double the volume of a canister, you would get half the pressure.
Charles's Law: V=RT or Volume = 8.314 * Temperature, simply put temperature is proportional to volume if moles and pressure are kept at a constant.
Avogadro's Law: V=Rn or Volume = 8.314 * Moles, volume is proportional to moles when temperature and pressure are held constant.
Gay-Lussac's Law: P/T=R or Pressure / Temperature = 8.314, temperature and pressure are proportional to each other assuming the other factors are constant.
All of the above can combine into the following equation:

Ideal Gas Law: PV=nRT or Pressure * Volume = Moles * 8.314 * Temperature, the end-all to the most basic of gas calculations to determine the behavior of gas factoring in a number of things. If you know all of these numbers but one then you can do some simple cross division to figure it out.
Simulated vs Unsimulated Turf
In SS13's code there is a distinction made between two types of turf: simulated turf and unsimulated turf. Simulated turf enables a lot of things, like lighting and construction, but most importantly it allows for gas calculations, meaning that this turf can be manipulated pretty much any way you want. This comes at the cost of being slightly resource intensive, at least when compared to its unsimulated counterpart, which does not process lighting, doesn't let you construct anything, and does not process gas; the gas that it's programmed is the gas that it maintains, and it has an infinite supply of this gas. The most obvious example of unsimulated turfs is centcomm: almost everything there, in order to save memory, is unsimulated since it's not a normal playspace. Another example is the asteroid, except an exception was made to allow it to process lighting and allow construction. It's vacuum state, however, will never change.

Getting to the point here, if an unsimulated turf is adjacent to simulated turf (namely floors), and that unsimulated turf isn't vacuum, then the unsim turf will keep the sim turf pressurized forever, resulting in an infinite supply of that gas. How likely you are to find unsim turf with special gas properties is very unlikely, but now you know.

ZAS
ZAS stands for Zone Atmospherics System, and is the atmos model that Aurora (and many other Baystation forks) use. It's primary distinction versus LINDA (the atmos model that most TG Station forks use) and FEA (Finite Element Analysis, only Goonstation uses it now) is that instead of performing atmospheric calculations for every single turf and generally being slow to the point that you can literally outrun a room depressurizing, ZAS will group turfs together based on whether or not air is allowed to flow between all of them and designate them as separate zones. This allows for larger and faster changes in atmosphere while being rather resource friendly. It also behaves a bit more realistically when it comes to rapid pressure changes. The tradeoff is that something like a canister of gas being opened in a room will flood the entire room with that gas instantly instead of spreading out over time. If you come from a non-Baystation forked server then this information may be privy to keep in mind.

Gas Gas Gas

Your typical canister UI.
This section here covers every possible gas that can enter the atmosphere. These are the only ones you have to worry about since there's no other gases programmed!

Oxygen canister.pngOxygen (O2): Oxygen is some crazy gas that most living things decided would be necessary to actually live, so now we're forced to breathe it, but not too much of it or you'll suffer oxygen poisoning and seizures. It's also evil, and it's required to start fires. Has a heat capacity value of 20, and a molar mass of 0.032 kg/mol.
Nitrogen canister.pngNitrogen (N2): Nitrogen is a gas that pretty much no one cares about and our bodies don't metabolize it, yet it makes up about 79% of our atmosphere and is inert. Interesting! Has a heat capacity value of 20, and a molar mass of 0.028 kg/mol.
Air canister.pngAir (Air): Actually just a mix of two gases at a concentration of 79% N2 and 21% O2, but it's this exact mixture that allows us to breathe normally. Theoretically you could replace the nitrogen with another inert gas and we'd still breathe just fine. If you want to sound like a nerd then call it nitrox.
Carbon canister.pngCarbon Dioxide (CO2): Carbon Dioxide is well known for being what we exhale out of our lungs, and it also usually comes about from a lot of combustion reactions. CO2 is toxic to crew in partial pressure concentrations of 7 kPa or greater. Has a heat capacity value of 30, and a molar mass of 0.044 kg/mol.
Nitrous canister.pngNitrous Oxide (N2O): No, it's not N20, it's N2O. Jamming twenty nitrogen atoms together would be stupid. Regardless, nitrous is often seen as a "sleep agent" in that its effect on most biological bodies is anesthetic. It is also an oxidizer, so it is capable of starting fires. Has a heat capacity value of 40, and a molar mass of 0.044 kg/mol.
Hydrogen canister.pngHydrogen (H2): Hydrogen is an extremely light gas that is inert and pretty much safe to breathe. It also happens to be a fuel, and its combustion leads to the formation of water. Isn't that interesting? Water can be described as the ashes of hydrogen combusting! Sadly water vapor isn't actually coded here so it just produces CO2 instead, which may make you question reality itself. Has a heat capacity value of 100, and a molar mass of 0.002 kg/mol.
Phoron canister.pngPhoron (PH): The mystery magic space gas. What does it do? Who knows, find out yourself! A few things that it does do, though, is poison biologics, contaminate clothing, and make you go blind. It's also a fuel, and an expensive one at that given the scarcity crisis. Has a heat capacity value of 200, and a rather chunky molar mass of 0.405 kg/mol.
Relevant Tools
It's said that tools are only as good as the person using them, but what if you have no tools? Well, you probably can't do much, then. Be sure to have some of these tools on your person if you plan to mess around with gas outside of breathing it.

Impactwrench.pngImpact Wrench: The impact wrench (or power drill, if you prefer) is a tool that condenses a screwdriver and wrench down into one tool. As you've probably found out by now, activating the item in hand will change its bit. For pipes you'll want a wrench bit in order to either secure or unsecure pipe sections and other devices. It cannot unwrench a pipe if its internal pressure exceeds 2 atm over ambient pressure.
Wrench.pngWrench: If you're missing an impact wrench then you probably have this instead. When it comes to pipe interaction there is no difference between this tool and its powered counterpart.
Pipewrench.pngPipe Wrench: As the name might imply this tool is specialized towards dealing with pipes. The pipe wrench's biggest advantage over other wrenches is that it can unsecure a pipe at any pressure. It's also able to mangle bend or straighten simple pipe segments if they are not already secured. This comes at the price of being unable to function like a normal wrench for anything other than pipes and atmospheric devices.
Analyzer.pngGas Analyzer: This tool is invaluable to any aspiring atmos tech. Though some may argue you should already have an innate sense of exactly what's inside a pipe via telepathy (you're the person in charge of that gas, you put it in that pipe!!!) this shouldn't stop you from deciding to use a tool like the analyzer. Once upon a time this device did pretty much nothing but now it can be used to measure the following:
Pressure
Temperature
Moles
Gas concentrations
It can also be used to analyze gas on the turf you're standing in by activating it in hand, and it can analyze tanks and other atmos devices as well.

Pipedispenser.pngPipe Dispenser: Despite the fact that this object cannot be held, it is still a tool. Put simply, when secured to the floor (with a wrench) in a powered area, this device will vend pretty much anything under the pipes subheading, giving you plenty of options. Oddly enough securing this to the floor is faster than unsecuring it. The more you know.
RPD.pngRapid Fabrication Device - Pipes: The handheld version of the pipe dispenser, the RFD-P is capable of... well, pretty much everything its bigger cousin can do, though with a smaller list of pipes and devices that can be created, heat exchange pipes most notably having gone missing. Activating the item in hand will bring up a list of pipes, and alt-clicking it will swap through device categories. The RPD requires matter cartridges in order to operate, but thankfully the ones that can be found in lockers are already loaded.
Extinguisher.pngFire Extinguisher: Yes, most fires come about from wacky gas interaction. Will this tool actually stop fires? Probably not, since this server uses Zone Atmospherics System instead of LINDA, but it can cool down superheated rooms significantly. Significantly. By several thousand degrees even. That's kind of nuts. Make sure to toggle the safety by activating it in hand before use!
Spaceheater.gifSpace Heater: A portable machine that can be programmed to either heat up or cool down rooms in a range between 0 and 90 Celsius, in spite of the name. The power cell can be removed by using a screwdriver.
Multitool.pngMultitool: Perhaps an unexpected addition, but the multitool actually does have a use in the land of pipes, as niche as it is. It is used to flip which overlapping pipe network a meter observes. For instance, if one network crosses from east to west and another network crosses from south to north on the same turf, and a pipe meter is secured over these pipes, using a multitool on it will swap between both pipe nets. Figuring out which is which is as simple as waving your gas analyzer over a network and comparing the readings.
Gasmask.pngGas Mask: Gotta have some PPE around here. This mask is capable of filtering out nitrous and phoron from the air, allowing you to breathe safely... assuming there's also oxygen in the air, since you kind of need that to live. Gas masks can also be used to setup an internal atmosphere. Older versions of this mask can be found in maintenance, though their filters are only effective against N2O.
Atmospherics VoidsuitFull.pngAtmos Voidsuit: A rather interesting piece of equipment, besides shielding you from the terrible effects of vacuum and other pressure-related hazards, it can also withstand considerable amounts of heat, up to 30000 Kelvin! Why? Who knows, but it trades radiation hardening for this feat.
Inflatables.pngInflatable Barriers: Easily one of the most important sets of tools to have at your disposal whenever you're dealing with atmospheric anomalies or hazards. If setup correctly in conjunction with emergency shutters, you can ensure that the room that you're entering a hazard zone from will remain safe and unaffected, provided you also use the inflatables correctly and don't just leave them open like a ding dong.
Emergencyshutter.pngEmergency Shutters: Important installations setup around every major doorway, these special shutters will fall shut whenever an air or fire alarm is tripped, shielding rooms from drastic atmospheric changes. They aren't perfect, and they won't shut immediately, so adjacent zones will still be effected, but it prevents further damage nonetheless. Shutters can be opened and closed freely if you have the correct ID requirements, or if there's no obvious danger on the other side of the door. You will otherwise have to crowbar it open. Shutters also have indicator lights representing the status of the room behind it. You can also examine shutters when you're close to them to see what the pressure and temperature is like on the other side.
Airalarm.gifAir Alarms: Stationary devices setup in almost every room on the ship, these idly wait for significant changes in atmosphere before sounding the alarm and slamming their shutters closed. Besides this their behavior can actually be programmed based on atmospheric qualities, and the vents and scrubbers that they control can be programmed from here as well. They can also be accessed and programmed remotely if their alarm is tripped. A tripped fire alarm will also allow this.
Alarm.gifFire Alarms: A bit more rudimentary compared to the air alarm, the fire alarm will only be a bastard at people smoking nearby trip if a fire shows up right in front of the alarm. No, not even a room with scorching temperatures will trip it; a fire has to be right in front of the alarm to go off. In spite of how useless this makes it, fire alarms can drop shutters if triggered, which can be useful if you're precognizant of any potential atmos anomalies, or if you see carp trying to break into the ship and risk depressurizing the room or something.
Pipes and Devices
Gas exists in the space around us. That space, in the context of SS13, is usually a bunch of rooms. What is a room but an exceptionally large container for gas? Similarly, pipes like to contain gas as well among other similar gas storage mediums. Some of these pipes and devices also help to get gas from one place to another easier! Below is basically every pipe and device you can get your hands on.

Basic Pipes

An example of different pipe types occupying the same turfs and facing the same directions.
Many of these pipes have distro and scrubber variants. You will need a pipe adapter to transition between pipe types. Note that almost all devices do not fit with non-standard pipes.

Pipestraight.pngStraight: The most common type of pipe you will see. It goes straight from one direction to another. It holds up to 70L.
Pipecorner.pngCorner: Effectively the same as the straight pipe, except it's not straight. Wow!
Manifold.pngManifold: A pipe with three ends on it instead of two. Holds up to 105L.
4waymanifold.pngFour Way: Even better than the previous entry, this one has four ends. Whooooaaaa. Holds up to 140L.
Cap: A bit that simply closes off the end of a pipe with a cap. There's no real reason to use this, especially since pipes don't leak, but it holds up to 35L regardless.
Z-Pipe: A pipe piece that connects one level to another. Holds 70L, but since you need at least two to make this work it's effectively 140L.
Pipeadapter.pngUniversal Pipe Adapter: This special piece of work will connect different pipe types together, namely normal, distro, and scrubber pipes. This can make for some rather creative pipe setups if you don't mind a few pipes being colored red or blue. Holds up to 70L.
Heat Exchange: Special pipe designed in a way to equalize heat with the gas inside and the environment that it's in. In other words, if you pipe super cooled gas into heat exchange pipes winding around a room that's normally at room temperature, then the room will cool down and the gas will heat up. Holds up to 70L.
Junction: Weirdly enough, pipe adapters cannot connect heat exchangers to normal pipes, requiring the use of this special pipe. On one end goes normal pipes and on the other goes heat exchange pipes. You can figure it out.
Insulated: Extremely niche pipes, these have no special use other than reinforcing pipes well beyond what's necessary. Only consists of straight pipes, meaning there's no manifolds or four-ways. Holds up to 70L.
=====Devices and Utilities=====
Every device available to you. This ranges from something as simple as a meter to a high power pump. Devices in green do not require power in order to function. Most devices that are powered will consume up to 150 watts when they are idle.

====Non-Pipe====
Pipe Meter: A device that will observe whatever pipe network it is secured onto. It will tell you the temperature and pressure of the network, even from a distance, and it even gives visual indicators of the pressure! This won't replace gas analyzers, though, since it can neither determine how many moles are in a net nor can it determine what gases are in the network. You can use a multitool to switch which network a meter pays attention to assuming it's secured over overlapping pipes.

Turf Meter: The pipe meter's slightly awkward cousin, this will measure the gas on the turf that it is secured upon. It's functionally similar to the pipe meter otherwise.

Gas Sensor: What could be considered an advanced turf meter, minus the visual indicators. In fact, this device requires a specific console in order to see what it's reading. It can determine pressure, temperature, and gas concentrations. You'll probably see these in the large gas chambers.

====Unary====
Connector: Definitely one of the most important utilities in any atmos setup, this will allow you to connect any portable atmospheric device to a pipe network with a wrench, typically canisters. Anything connected to one of these will automatically balance the gases between the connected device and the connected pipe network.

Heat Exchanger: Not to be confused with the heat exchange pipes seen above, this radiator is designed to face another heat exchanger in order to balance heat between two networks without actually mixing the gases together.

Tank: A massive, immobile tank of gas that has a capacity of 10000L. They can neither be built nor deconstructed. They're rarely if ever seen unless ordered from Cargo or found on an installation that doesn't have gas storage chambers. Not to be confused with canisters or small handheld tanks.

Gas Cooler: A large device that is capable of cooling the contents of a pipe network to near-Absolute Zero values. How fast it cools and how large its volume is depends on upgrades made to it. Holds 600L by default.

Gas Heater: A large device that is capable of heating the contents of a pipe network to rather high values. How fast it heats and how large its volume is depends on upgrades made to it. Holds 600L by default.

Air Injector: A device whose whole purpose is to pump gas (not just air, like the name implies) onto a turf, similar to a vent pump, except it's rated to pressurize up to 15000 kPa. Usually controlled from a special console. Holds 700L, allows a flow rate of up to 700L/s, rated to pressurize up to 15000 kPa, can consume up to 15 kW at max operational capacity.

Vent Pump (Unary Vent): The device that you'll probably see the most around the ship, these vents are typically controlled by an air alarm to determine what pressure to target. Special versions of this vent allow it to siphon gas indiscriminately instead, a notable example being the vent pump in the SM core. Vents performing both functions can be found in airlocks. Holds up to 200L, allows a flow rate of up to 200L/s, rated to pressurize to 7500 kPa, can consume up to 7.5 kW at max operational capacity.

Scrubber: Where a vent pump (usually) pumps a gas (typically air) into a room, scrubbers do the opposite, with a twist: they can be controlled by an air alarm to target and collect any type of gas and pump it into a pipe network while leaving other gases alone. It can also be set to forcefully siphon gas indiscriminately, giving it a lot more power. Holds up to 200L, allows a flow rate of up to up to 200L/s, 2500L/s on siphon, rated to pressurize to 7500 kPa, can consume 7.5 kW at max operational capacity.

Cryo Cell: Maybe not immediately concerning to your average pipe enthusiast, the cryo cell is nonetheless an atmospheric utility. It's connected to a pipe network that hopefully has chilled oxygen, which can be used to put a patient in stasis and heal some of their wounds. See the guide to medicine for more info.

====Binary====
Pressure Regulator: An often overlooked device, this programmable gate allows for a number of tasks. It can be programmed to allow gas through until the output end is greater than or equal to the target pressure, or it can be programmed to allow gas through when its input end reaches the target pressure, and will stay open until the input end is less than or equal to the target pressure. All of this comes at the cost of being unable to pump gas; if its input is at a lower pressure than the output, gas cannot flow through. In order to allow the regulator to do its job the valve must be unlocked. The end with the bright red valve is the output end. Both ends of the regulator hold 500L, making this effectively 1000L, allows a flow rate of up to 500L/s.

Manual Valve: A simple gate that allows you to connect two networks together or shut them off from each other. Note that neither the AI nor its borgs can operate these valves. It also contains no volume, oddly enough.

Digital Valve: Exactly the same as the manual valve, except it cannot be unsecured, for reasons beyond comprehension. It also cannot be vended from a pipe dispenser. If you carefully observe where these valves are located you might be able to determine what their true purpose is. They can also be operated by the AI and its borgs.

TEG Circulator: This is just one part of a thermoelectric generator. Basically it takes gas in on one end and outputs it on another end. Which end is what can be determined by examining the circulator. Each end holds 200L, making this effectively 400L, allows a flow rate of up to 200L/s (probably).

Gas Pump: A strong staple in any pipe setup, this will attempt to force gas on its input end into the output end for as long as the gas on the output end is at a lower pressure than target, and there is gas in the input end. The pump is smart and will just let gas through if the output end is at a lower pressure than the input end, but the pump's effectiveness will decrease dramatically if the pressure on the input end is well below the pressure of the output pipe. The output end is the bit with the red stripe on it. Each end holds 200L, making this effectively 400L, allows a flow rate of up to 200L/s, rated to pressurize to 15000 kPa, can consume up to 7.5 kW at max operational capacity.

High Power Pump: The big sister of the gas pump, the high power pump can force gas from one network into another a bit faster. The output end is the bit with the red stripe on it. Each end holds 200L, making this effectively 400L, allows a flow rate of up to 200L/s, rated to pressurize to 15000 kPa, can consume 15 kW at max operational capacity.

====Ternary/Quaternary====
T-Valve: A bit of an odd specimen, this valve has one input and two potential outputs, but at least one of them will always be closed, and neither of them can be open or closed at the same time. The indicator lights will tell you which side is open and which is closed, and turning the valve will toggle which output is opened. The AI and its borgs cannot operate the valve. There is also a mirrored variant.

Digital T-Valve: Functionally identical to its manual sister, but it cannot be unsecured from the floor wherever it is found, and it cannot be vended from the pipe dispenser. The AI and its borgs are able to operate the valve. There is also a mirrored variant.

(Omni) Gas Filter: The gas filter is an impressive device that is capable of pumping gas through to another network while scrubbing a target gas out into a different, perpendicular network. A series of these set to different gases is what allows the filtering line of Atmospherics to function. There is a mirrored variant of this device as well. There is also a much more flexible omni variant, which allows you to set which side is the input, output, and allows you to set two more sides as filters. Each programed side holds 200L, making this effectively 800L assuming an omni filter is set to have all four sides in use, allows a flow rate of up to 200L/s, rated to pressurize up to 7500 kPa, can consume up to 7.5 kW at max operational capacity.

(Omni) Gas Mixer: As the name implies, this device mixes gas together, usually by taking two input gases (which can already have been mixed up by something else) and outputting the combined result into a pipe with programmed concentrations. One of these devices is what allows the air line of Atmospherics to maintain a strict 79% N2 21% O2 air mix. There is a mirrored variant of this device as well. There is also a much more flexible omni variant, which allows you to set up to three inputs and one output. Each programmed side holds 200L, making this effectively 800L assuming an omni mixer is set to have all four sides in use, allows a flow rate of up to 200L/s, rated to pressurize up to 7500 kPa, can consume up to 7.5 kW at max operational capacity.

====Portables====
Everything here (with the exception of the space heater) can be connected to a connector to balance gas contents between the portable and the pipe network that the connector is secured to. None of these devices need to be turned on or have their settings altered in order for this to be accomplished.

Canisters: Probably the most common form of portable atmospherics, a canister can hold up to 1000L of gas, and (miraculously) can withstand an infinite amount of pressure and temperature. This doesn't mean they're indestructible - they can rupture due to explosions nearby... or just because a random event told it to rupture. Canisters are typically pressurized to 4560 kPa as a standard. They have their own internal pressure regulator rated up to 1013 kPa, and can either be allowed to pressurize its turf and surroundings up to that pressure (assuming it has enough gas) or it can be used to fill handheld tanks up to that pressure. You can also change the color of the canister by emptying it and pressing the "Label" button. Not to be confused with handheld tanks or the much larger tanks which sort of accomplishes the same goal.

Portable Air Pump: Basically a fancier canister, but with a pump, rated to pressurize up to 1013 kPa, at a rate of a whopping 1000L/s! Air pumps are typically pressurized as high as possible with room temperature air (about 6157 moles of air) to facilitate refilling depressurized rooms. This is capable of pumping gas out into surrounding turfs or pumping gas into itself from surrounding turfs. Pumps, of course, require power, hence this device possessing a power cell. The cell can be retrieved by screwing it out. The pump can both fill or empty a tank inserted into it. Can hold up to 1000L.

Portable Scrubber: This particular curio is basically a non-programmable scrubber that will scrub anything that isn't nitrogen or oxygen from the air. Its pump is rated to pressurize up to 1013 kPa at a rate of 200L/s. It will not use power if it is turned on and there are no gases to scrub. It will scrub contaminants (anything that isn't oxygen or nitrogen) from any connected tank while turned on. Like the portable air pump, this too requires power, and has a power cell that can be replaced by screwing it out. Holds up to 750L, allows a flow rate of up to 200L/s.

Hydroponics Tray: Bet you weren't expecting to see this here. It's true, plant trays do have gas interactions which can be controlled by hooking it into a connector and flipping the lid down. The plants (assuming they're mutated and not dead) will passively generate gas, and are capable of outputting this into pipes if the tray is connected to a pipe network. The tray is capable of holding up to 100L.

====Handhelds====
Any handheld item that can store gas will be under this heading. This is usually in the form of tanks, but jetpacks are also here. Tanks can only be pressurized up to 30 atm (3039 kPa) before its pump/regulator begin to involuntarily leak gas out. 40 atm (4052 kPa) will result in a rupture. You can tell how much pressure is inside by activating the object in hand. You can also examine the item to determine how hot it is.

Oxygen Tank: Probably the most common tank seen on the Aurora, this simply holds pure oxygen. It can hold up to 70L, and its release pressure is set to 21 kPa by default. It can be worn on your back. This tank may be seen in multiple colors, such as yellow, red, or more rarely brown.

Anesthetic Tank: General anesthetic in gas form, filled with nitrous oxide and oxygen. Using these as internals will probably put you to sleep. Medical won't use these too often.

Air Tank: Similar to the oxygen tank, but it contains an air mix instead. Because the O2 is in a lower concentration, the release pressure is set to 101 kPa, meaning this tank will not last as long as a pure oxygen tank.

Emergency Oxygen Tank: The small tank that almost everyone spawns with in their emergency internals box. This, too, contains pure oxygen, but it can only store up to 2L of gas, making this a very, very small tank. There is a yellow version that is slightly bigger and holds 6L, and an even bigger version that holds 10L. These can be worn on your belt or put in your pocket.

Jetpack: These jetpacks can be used to maneuver in zero gravity environments freely, and can even traverse z-levels if used correctly. They can also be used as internals. They can be filled with anything, but usually only oxygen or carbon dioxide is used. Holds up to 70L.

Phoron Tank: A tank full of Phoron. Who could've guessed? Can be used as internals, so beware. Holds up to 70L.

Hydrogen Tank: A tank full of hydrogen. Holds up to 70L.

====Unimplemented====
Everything in this category exists, but cannot be found on the ship. For posterity's sake all unimplemented devices will have their basic functions described in case they do, in fact, return to use.

Passive Vent: Effectively just a pipe that's allowed exchanging gas contents with the turf it's secured upon. As you can imagine, a passive vent connected to an empty pipe exposed to a turf of air will fill the pipe with air. 

Binary Vent Pump: Basically a vent pump, except it has two ends where you can connect pipes. One end is the input - for when it's pumping gas into a room -, and the other end is the output - for when the vent siphons gas instead. 

(Gas) Synthesizer: Requires Synthesis tech. As the name implies it produces a specific type of gas as output, using raw energy as input. The holodeck works on similar technology. Normally connected to a pipe on one end.

Thermal Plate: One may believe that this was a precursor to the heat exchange pipe, but this was actually created afterwards. This is connected to a pipe on one end and exchanges heat with the turf it was secured on. You would need dozens of these with some awkward pipe work to accomplish what simple spaghetti HE pipes can accomplish now.

Thruster: Ejects gas to produce thrust for shuttles. The ship version is much larger but based on similar principles, as are fightercraft and dropship thrusters.

Pipe Turbine: A condensed version of the gas turbine. It would produce energy by piping extremely high pressure gas (usually superheated) to turn a turbine in order to generate power, assuming it's connected directly to a special generator. 

=====Air Alarm Operation=====

An air alarm's interface set to the sensors screen. You can adjust alarm thresholds here.
Air alarms. They alarm when there's no air... sometimes. The fact of the matter is that air alarms are a lot more flexible than you think, and it's this flexibility that propels their potential to be a very powerful tool to greater heights. By default, an air alarm's purpose in a regular old hallway is to make sure that the air pressure is okay, that there's enough oxygen concentration, there aren't dangerous quantities of toxins or fuel in the air, and that the temperature isn't extremely hot or cold. If any of that fails to meet the programmed criteria then the alarm will trip, dropping the emergency shutters that it's in charge of, and informing nearby alarms to do the same in order to localize the damage to a specific set of rooms, protecting the rest of the vessel from atmospheric hazards. If the emergency involves depressurization then it'll also shut off its vents and scrubbers to conserve resources.

An air alarm can be accessed either in person or remotely via an air alarm monitoring console. If you are accessing it in person then you will need to swipe your ID over it to unlock its controls. If accessing remotely then all you need is a console with the atmosphere control program (and a valid atmos tech ID to open that program, but you don't need it if it's already open) and for the air alarm to not have its remote control setting set to "Off". With that out of the way, here are the intricacies to operating an air alarm:

====Basic Interface====
The first thing you'll see towards the top of the interface - and you will always see this no matter what menu you navigate to - is the gas composition that the alarm is reading. In particular, it will tell you the following:

Pressure: How pressurized the room is, simple enough. By default, pressures below 81 kPa and above 122 kPa are deemed harmful and will trip the alarm.
Oxygen: The concentration of oxygen in the room. It won't tell you exactly how much is in the room, but it does give you a percentage, and since you already know the pressure, you can probably guess how much is there. Partial pressure values below 16 kPa and above 140 kPa are deemed harmful and will trip the alarm.
Carbon Dioxide: The concentration of CO2 in the room. Ideally this should be zero, but some is harmless anyway. Larger concentrations, however, are harmful to breathe. Partial pressure values above 10 kPa will trip the alarm.
Phoron: If this is in the air then something has probably gone wrong. Trace amounts of Phoron are safe to breathe and are a negligible threat to most crew, but it doesn't take much more to make it harmful. Partial pressure values above 0.5 kPa will trip the alarm.
Hydrogen: By contrast to Phoron, hydrogen is actually completely safe to breathe and is inert. It is, however, still a fuel and will start fires if exposed to heat and oxygen (which air has plenty of), so it is a hazard all the same. Partial pressure values above 0.5 kPa will trip the alarm.
Other: Since nitrogen is ignored by air alarm thresholds outside of calculating pressure, "Other" is nitrous oxide by process of elimination. This category is hidden from the rest of the list until it is made relevant. Nitrous, while not terrible harmful to crew, still possesses anesthetic properties and can force people to fall asleep, even in small concentrations. Partial pressure values above 1 kPa will trip the alarm.
Temperature Put simply, temperature of the air measured in both Kelvin and Celsius. 20 Celsius is usually what you'll find most rooms at, aided in part by the air alarm's thermostat. Temperatures below 247 Kelvin (-26 Celsius) and above 339 Kelvin (66 Celsius) will trip the alarm.
Local Status: The quick and simple way to check if everything is within acceptable, programmed bounds. Does this mean the room is actually safe? Not always!
Area Status: If an air alarm in a nearby room has tripped an alarm then this value will say so. If this value reports that there is an alarm nearby then it, too, will also assume that there is something wrong and shut its shutters.
Other interface buttons are the remote control buttons, which allow you to allow or deny remote access to the air alarm, good if someone's being a dummy with the controls in Atmospherics. You can also adjust the thermostat between 0 and 40 Celsius, though heating and cooling the room takes a while to accomplish, and is handled by the air alarm itself and not the vents.

=====Scrubber Control=====
If there's wacky atmospheric anomalies that are making the air the crew breathes something that the crew would rather not breathe, then scrubbers have you covered, assuming they're present in the room affected by bad gas of course. This menu shows you every scrubber under the alarm's control, and it will allow you to turn specific scrubbers on or off, set specific scrubbers to assume normal operation or indiscriminately siphon gas immediately, and they can be programmed to scrub any gas from the atmosphere. By default, carbon dioxide is the default setting on all scrubbers. With careful manipulation you can solve a lot of atmos crises with simple scrubber programming. Canister of nitrogen ruptured and ended up overpressurizing a room and upsetting the air balance? Why set the scrubber to panic siphon when you can just turn on nitrogen scrubbing instead? Much cleaner that way.

Vent Control
A menu similar to the scrubber menu in that it lists every vent pump under the alarm's control, but vents are a bit different in how they can be programmed. First off, individual vents can be turned on or off, so there's that. Secondly, there are a few rather esoteric toggles and values here that do the following:

External Pressure: This setting will have the vent check the pressure of the room that it is in and attempt to pressurize it to what's programmed in the external pressure bound variable. This is the default setting.
Internal Pressure: This setting, by contrast, will check the pressure of the pipe network that the vent is connected to, and the vent will pump gas out until it reaches the pressure programmed in the internal pressure bound variable. This setting is not recommended for normal life support functions.
External Pressure Bound: This coincides with the external pressure check. If the pressure of the room is lower than this value then the vent will open. Otherwise it will remain closed. This is set to 101.3 kPa by default, and this value can be reset easily with the "Reset" button.
Internal Pressure Bound: THIS VARIABLE CANNOT BE MODIFIED. In theory this would allow a vent to remain open until the network it's connected to reaches the target pressure, otherwise it remains closed. This is set to 0 kPa by default, and because it cannot be modified, the vent will remain open until the pipe it's connected to is vacuum. Using this setting on the distro network will functionally keep the vent open forever.
Environmental Modes
This menu provides some quick premade settings that make the air alarm and its connected devices function in particular ways. Most have their uses, one is completely useless. Here they are:

Filtering: The default setting of pretty much every air alarm, this turns on all vents and scrubbers. Rooms are pressurized with air and contaminants are scrubbed. Vents are reset to default values, but scrubbers preserve all but the CO2 setting.
Replace Air: This will set the scrubbers to siphon and indiscriminately scrub all gas from the atmosphere, but will keep vents open. Depending on the ratio of vents to scrubbers, the room can easily depressurize due to the flow rate of a siphoning scrubber. Can be useful as a lazy way to regulate a room's temperature.
Panic: This shuts off all vents and forces all scrubbers to siphon gas. It will continue to siphon until it is told to stop by a user. The scrubber loop probably won't enjoy this. There is also a big yellow button on the main menu that lets you select this option.
Cycle: This will turn off all vents and set the scrubbers to siphon until the room is down to 5 kPa, at which point it will flip over to Fill mode.
Fill: This will turn off all scrubbers and enable all vents. Unless the scrubbers have been programed incorrectly (a problem that is easily fixed), there is no real reason to use this mode: it does not make vents operate faster. Just use Filtering instead.
Off: What is says on the tin. All vents and scrubbers will switch off and do nothing until the user says otherwise. This option is selected automatically if a depressurization event occurs.

=====Sensor Settings=====
The last menu, this is the screen that determines when and for what the air alarm will trip. You'll notice that all of the thresholds listed here are also represented by the air status at the top of the interface. Each category possesses four categories: minimum warning (min1), maximum warning (max1), minimum alarm (min2), and maximum alarm (max2). Warning thresholds will alert alarm consoles that something is beginning to exceed programmed thresholds and the alarm will flash yellow. Alarm thresholds will shut all emergency shutters and seal off rooms in an attempt to prevent atmospheric hazards from spreading. Many of these thresholds represent partial pressure, and can be modified with the fact that they are pressure values in mind. The temperature value, on the other hand, is programmed based on Kelvin.

Some thresholds also report that they are "Off", or otherwise not concerning themselves with measuring minimum/maximum thresholds. You can set this yourself by setting a value to "-1", which will turn that specific sensor off. You can also turn minimums and maximums off by setting that same value on the "min2" and "max2" values. Doing this for everything can keep an alarm from tripping in spite of changes in atmosphere.