Oxygen

Oxygen is the 8th element in the known periodic table. While oxygen is the third most abundant gas on Earth, its abundance in the Hellion system may vary. Critical for respiration (breathing) and vital bodily functions, oxygen will be the most constant resource you'll need to maintain next to power. Thankfully, it is replenishible through various organic sources, such as water and ice. However, while it is needed for breathable atmosphere, it also facilitates combustion. In the event you do not have a fire extinguisher to suppress a fire, you can depressurize a room to suck the oxygen out of the room and kill the fire.

Converting oxygen from raw resources to breathable gas requires first mining raw materials (Ice & Dirty Ice), refining through proper equipment, and released into station modules via the Life Support Systems or stored in suit packs and refilling canisters. If resources permit, try to keep some reserves of oxygen on hand, especially in the form of filled EVA suit packs for emergencies.