Oxygen & Hydrogen

Humans and similar aliens require Oxygen to breath - and, therefore, to live. Additionally, areas zoned for Oxygen atmospheres will require some overhead just to ensure proper pressurization (e.g. every 20 tiles, rounded up, requires 1 Oxygen). (Note that this ratio is not meant to represent any particular atmospheric ratio, as units are deliberately unspecified and meant to vary from one resource to another, it is merely a gameplay element.)

Areas that become isolated from Oxygen producing systems will slowly lose Oxygen, leading to anyone within them dying.

Hydrogen-breathing aliens have similar needs for Hydrogen, as do areas zoned for Hydrogen atmospheres.

User Story

An Event occurs that results in a hull breach in a room. The station will automatically seal the adjoining doors to isolate the breach, immediately robbing the breached room of Oxygen. Anyone inside suffocates and dies. Due to the layout of the station, this breach has isolated 3 rooms that no longer can draw a path to any system that produce Oxygen, and as a result Oxygen levels in those rooms gradually decrease, eventually suffocating anyone within them unless Oxygen is restored to these rooms (e.g. by creating a new path for Oxygen to reach them, building a new system that produces Oxygen, or fixing the breach and reopening that path).