# Difference between revisions of "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 how Atmos works the way it does, making you ready for all kinds of situations.

Better start learning Russian kiddo.

## 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

Our first base gas is Oxygen. All humans, pets, and lizard-people 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.

### N2

Our second base gas is Nitrogen. Not particularly more heat absorbant 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.

### Air

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

Air in SS13 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.

### 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.

### Plasma

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

Plasmafires use oxygen and plasma to produce heat and waste gas. Energy released from plasmafires depends on the burn rate for plasma. The plasma 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 Plasma, with the air temperature exceeding the upper limit of 1643.15 Kelvins. Oxygen is burned at 0.4x the rate of plasma 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 plasmafires are either solely tritium on oxygenated plasmafires (more detail on the tritium section below) or water vapor and CO2 on a 3 CO2 : 1 H2O ratio on non-oxygenated plasmafires.

### 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.

### Tritium

Radioactive, flammable gas that is used in plenty of chemical reactions. Created by heating loadsa O2 with Plasma. Also, radiation collectors convert plasma into this. Tritium, though not naturally radioactive, releases radiation when it is burned. 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 many 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 wont be as theatrical as the first one.

Export price per mol: 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 tritiumfires and unsaturated plasmafires.

### 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 electrolizing Water Vapor with an electrolyzer machine. Hydrogen is solidified in a reaction with BZ as catalyst at high heat and pressure (over 1e6 for both) to produce metal hydrogen , which can be used to make armor, a fireaxe , and golems.

Export price per mol: 1 credits

### BZ

BZ gas is a potent hallucinogenic that also put slimes into stasis, degenerates changeling chemicals and supresses their hivemind. As a side effect, affected people will take low brain damage.

BZ is formed in an exothermic reaction when 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: 4 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!

Formed by irradiating tiles with 2 part CO2 1 part O2 in the air. The Supermatter can be used to naturally generate a small amount of pluoxium if CO2 is added to the cooling loop, but this is risky.

Pluoxium may also be created by exposing O2, CO2 and Tritium together in an endothermic 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: 5 credits

### Miasma

Miasma (bad air) is created from rotting corpses, gibs, and other things. Miasma smells bad and can cause diseases to spontaneously appear. The higher concentration of miasma in the air, the higher level symptoms can appear.

Export price per mol: 2 credits

### Nitryl (NO2)

Nitryl (formerly Brown Gas) speeds you up while causing lung damage. Nitryl is made by combining a minimum of 10 moles Oxygen, 10 moles Nitrogen and 5 moles BZ in a (slightly) exothermic reaction between 1500K and 10000K. The consumption ratio for the reaction is 20 N2 : 20 O2 : 1 BZ. Higher heat improves the rate of reaction.

Nitryl decomposes when in contact with Oxygen under 600K, splitting into a 1:1 mix of Nitrogen and Oxygen. Meaning you will have to experiment to find a way to breathe nitryl and not suffocate while doing so if you wish for speed.

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

### 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 40 moles Plasma, 20 moles CO2, and 20 moles BZ in a endothermic reaction at temperatures above 473.15 K. The consumption ratio for the reaction is 6 Plasma : 3 CO2 : 1 BZ. Higher heat improves the rate of reaction.

Export price per mol: 15 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 energy (exothermic) and BZ works to reduce the energy released. 2:1 Nitrogen to Tritium is about optimal here.

Export price per mol: 5 credits

### Proto-Nitrate

Proto-Nitrate is a highly reactive gas, but non-toxic when breathed. It is created in an endothermic 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 cause localized hallucinations in an exothermic reaction

When between temperatures of 150-340k, Proto-nitrate reacts with tritium to produce H2

Proto-nitrate reacts with at least 150 moles of H2 to create more Proto-nitrate in an exothermic reaction

Proto-nitrate explodes when exposed to Zauker.

Export price per mol: 5 credits

### Halon

Halon acts as a fire suppressant by removing oxygen in the air (while producing CO2) in an exothermic 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 by combining BZ and Tritium in an endothermic reaction between 30-55 K. Tritium is consumed at around 16x the rate of BZ.

Export price per mol: 9 credits

### Healium

Healium is a red gas which acts as a stronger sleeping agent than N20, 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.

Export price per mol: 19 credits

### Stimulum

An experimental gas that makes you stun and sleep immune and slightly regenerates stamina, but also causes toxin damage the longer you've been breathing it (current cycle x 0.1 toxin).

Formed by combining Tritium with Plasma, BZ, and Nitryl, then heating it. Also formed in high quantities by fusion.

Export price per mol: 100 credits

### Zauker

Zauker is an incredibly deadly gas if inhaled. It is made by mixing Hyper-Noblium and Stimulum in an endothermic reaction at temperatures between 50000-75000 K. Stimulum is consumed at around 50x the rate of Hyper-Noblium. It is worthy to note that 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: 1050 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
Emergency Oxygen Tank 3
Extended Emergency Oxygen Tank 6
Double Emergency Oxygen Tank 10
Oxygen Tank (blue/red) 70
Plasma Tank 70
All pipes 70
Pipe manifold 105
Locker 200
Coffin 200
Gas Pump (each side) 200
Volumpe Pump (each side) 200
Passive Gate (each side) 200
Heat Exchanger 200
Gas Filter 200
Vent 200
Scrubber 200
Layer Manifold 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): 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
Nitryl 20
Freon 300
Hypernoblium 2000
Proto-Nitrate 30
Halon 175
Healium 10
Stimulum 5
Zauker 350

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.

## 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. A pipenet is any collection of normal pipes connected together, including some sub types. Counter to pumps, it experiences no delay in its gas transfer. It essentially acts as a pipe, which, as all pipes, transfers gas instantly to all connected pipes. 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 equalise 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 equalises 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.

### 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.

### 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 heat exchange pipes system.

### Filter

The filter is the first device that connects 3 pipenets. It can be set to a single gas, and it will dump this gas 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 pas. 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 ouput, 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, mol-wise. This will give you scuffed ratios if you do not equalise temperatures, if you need the precision, make sure they're equal.

### Heat Exchange pipes

Functions like regular pipe, however, this will attempt to equalise 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 12.7K.

### 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 equalise 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 Manifold

Connects the 5 different layers of pipenets. 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.

### 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!

## Atmospherics Layout

 A wise Atmos Tech once said: "just stare at the pipes until you get it." "Simplified" picture of the Atmospherics pipe system. Yellow circles represent filters and the lightbrown circle represents the mixer.

Here are two pictures of the atmospheric pipe system. Right one is a "simplified" version of the left picture. Yellow circles representing the filters which filter out a certain gas from the Waste In -gasmix. The light yellow circle near the lower middle represents the mixer which mixes N2 and O2 into a breathable air mix.

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.

The tanks (the small rooms in space just outside of Atmos) of the station's atmospherics network, unlike in the rest of the station, are 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:

1. The gasses are pumped through the cyan tubes from their respective tanks (N2, O2).
2. They are mixed in the air tank (Air) to a 1/5 mix of O2 and N2.
3. The breathable gas is then pumped through the cyan loop to the north of Atmospherics.
4. 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:

1. Scientist Bill messes up and fills the Toxins Lab with plasma but fortunately manages to evacuate the room safely.
2. 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.
3. 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.
4. 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.
5. The plasma finally reaches the Plasma Filter.
6. Here the plasma gets extracted from the waste gas and pushed into the big plasma tank-room outside the windows.
7. The plasma stays in the room until someone decides to pump it out.
8. 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 two machines at the top can dispense infinite pipes, and your wrench can disconnect and connect pipes to each other. the better option, of course, is to use the rapid pipe dispenser that will spawn in atmospheric technician lockers and the engine room on some maps which can create and destroy infinite pipes.

The dumbass-version of the Atmospheric pipe system. See the steps what each colored circle means.

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 style how to set up the pipes, there are many ways and they all have their own pros and cons!

• For the love of Nanotrasen, at least do this:
1. Get a Volume Pump from the Pipe Dispenser at the north side of Atmos 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!
2. Set all red circled filters ON and set them to maximum pressure (200 L/s) so waste gases will actually be moved.

• This is good as well:
1. Go through the N2 and O2 (besides southern wall) and set their output to 4500 kPa.
2. Set the pumps next to the computers at 4500 kPa also, so the gases being pushed out of the gas-room get moved fast too.
3. Set the Air-computer's output to maximum (4500 kPa).
4. 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.
+ 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.

A little safer, but not as efficient, way of setting up the system is leaving the blue circled 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 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.

## 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 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 (more air pumps can be found from the locker room).
• Make extremely extended oxygen tanks for internals use (instructions below).
1. 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.
2. 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.

### Optimizing Internals

• On a basic view, a 16 kPa minimum O2 requirement in internals. Pure O2 is theoretically toxic in real life, but has no representation for this in code, and 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 are largely capped by the 1000 kPa release pressure, 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, set your output pressure to 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 brigs distribution system is set up to be potentially independent of the rest of the station's distribution loop, maybe other places can be set up like this as well?
• 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 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.

## 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).
• 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.

## Useful Atmos Trivia

• Your holobarriers let people walk through, yet block gases. Very useful for cleaning up Plasma spills, fixing hull breaches and keeping fires in check.
• 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 one tile, which is known as 'sequesteral' 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 heated Plasma in a canister, with an O2 tank placed in the canister, and then open the valve between them. You will also need to run very, very fast.
• 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.

## Fusion

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 6: "Chaos Hyper-Torus Edition".

The quick guide to make fusion in version 6 is:

• Mix at least 250 mols of CO2 H2, at least 250 mols of plasma and a "good amount" of tritium. Then heat it all to over 10000K.
• Many gases have a "fusion power" stat that may affect a fusion reaction when present. You can find this stat by looking directly in the "code".

For a more detailed description of how fusion works and what you can create with it, you may need to try to understand the pull request that last changed it (as of April 2020) combined with the "original pull request", or find other sources.

Click expand to see the old outdated version 5: "Power Tiered" fusion system.

Fusion occurs when you give plasma and tritium a lot of heat energy. It'll quickly convert all of the gases to an extremely hot mixture based on the power of the reacting mixture. This power can be increased or decreased depending on what exactly is in the mix. The ratio of plasma is kept at exactly half of the mix for higher power and the rest of the gas, the mediation gas, should have a high fusion power and a low average specific heat.

Gas fusion power: Each gas has a different amount of power it can contribute to the fusion process per mole, typically the rarer it is the stronger it will be. If it isnt listed here, it doesn't provide any power to the equation but can still be used to lower the average heat capacity or required temperature.

Gas Fusion power
CO2 1.25
Water Vapor 8
Nitryl 16
BZ 8
Stimulum 7
Pluxonium 10

Power ratio formula: When fusion occurs and plasma is exactly half of the mix, the following formula is used to find the tier of the fusion:

If plasma is not half of the mix, it will begin a bell curve decay in the power ratio.

Required Temperature: 3e9 joules must exist in the mix for the fusion to occur

Power tier Depending on the power you create from the mixture, fusion can go into 4 different tiers scaling to have typically higher rarity in produced gas, energy produced, and dangerous side effects such as radiation bolts, lingering radiation, tesla shocks, and an explosion. A portion of the gas is converted to raw energy, growing depending on tier.

• Low tier:
• 0-5 power ratio
• Low chance of explosion and short range shock
• Produces 10% BZ and 90% CO2 with a high enough heat to make a tiny amount of hyper noblium

• Medium tier:
• 5-20 power ratio
• Moderate chance of explosion and medium range shock
• Produces 25% Nitryl and 75% N2O with a high enough heat to make several hyper noblium bombs

• High tier:
• 20-50 power ratio
• High chance of explosion and wide range shock
• Produces 1/12th Stimulum and 11/12th pluxonium with a large amount of heat

• Super tier:
• 50+ power ratio
• 100% chance of explosion and very wide range shock
• Produces 100% Tritium with a massive amount of heat

Example Since fusion tends to be a little difficult for people to find entry to, a sample for doing so will be provided here.

• mix: 5000 moles of trit, 5000 moles of plasma.
• Average mediation specific heat: 10
• Average mediation fusion power: 1
• Mediation mole count: 5000
• Fusion power:(5000*1)/(10*80) = 6.25 = medium tier
• Required heat: (3e9)/((average specific heat)(total moles)) = 2857.14 k

Tips for working with fusion:

• at the highest efficiency roughly 30% of the gas you use will be lost to the pump to the canister and to the heat exchanger to the can so prepare accordingly.
• Work with friends. It has high setup and maintenance requirements, and your fellow atmos techs, engineers and toxins scientists are all valuable resources in your pursuit of very hot things.
• Although some gases may have high fusion power they might have too high specific heats to give you the tier you want, as a rule of thumb Stimulum, Nitryl, and BZ are all very useful for reaching higher tiers of fusion.
• Fusion requires Heat energy not Temperature meaning the more moles you can fit into an area, the lower the temp is for you to start fusion.
• It is recommended to have a sacrificial lamb preform the finale in an unused area such as space, if not be wearing radiation protection and have an excuse for the gods you are about to anger.
• It is intended to preform fusion in a canister but doing it in a pipe net or incinerator is possible.
• Heat exchanges are your friend for starting your reaction. Connect it to tritium burn chamber or canister to get the heat needed to start it.
• Typically gases with high power but also high specific heats like water vapor or pluxonium will become exponentially more efficient the more you use due to the average specific heat increasing less and less the more you use.
• Should you want to release a canister that you used for fusion in a room full of people, consider shooting it to break it open so you arent right next to it.

Beyond the basics:

• You can harness the radiation produced from fusion to produce power using rad collectors. Earn your keep as a member of engineering. Or just use it for pluoxium production.
• The higher the temperature, the prettier the fire. See if you can get the prettiest color fire.
• Traitors can harness fusion reactions to devastating results if done correctly.

## Being a Traitorous Scum

Or: How to get the AI lynched; How to call the shuttle as Atmos Tech, step-by-step:

1. Open valves connected to harmful gas you want to add to the station.
2. Set pumps to the distribution loop to maximum pressure output (4500 kPa).
3. 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).
4. Open valve from custom mix chamber.
5. Turn on pump leading to distribution loop.
6. 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).
7. 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:

1. 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.
2. Open the valves for your deathgas mixture of choice.
3. 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:

1. Reconfigure the piping to connect the waste system directly into the pure pipes.
2. Find a place with a waste pipe next to a distro pipe, then configure them so that they can be united later.
3. Open the valves for your deathgas mixture of choice, the waste piping should now begin to fill with your gases.
4. Set as many air alarms as you can to have every vent at Internal 0.
5. When ready, go back to your distro/waste pipe spot and unite them.
6. 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 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.