Simplistic air/contamination flow between rooms

So i'm looking to create a system where the rooms in my game (topdown 3D if that matters) have a certain amount of oxygen and possibility of contamination (such as fire or gas) and i wanted to allow for this to spread as needed.

Since my entire game is rooms and corridors my though is to group each rooms static elements (The prefabs the make the walls and floor) under a game object called Room. This would then have a script that manages the amount of air in the room and the contamination. it also keeps track of doors that link to this room. And those doors have a script that will notify when the door is opened or closed.

This way each room knows how much air it has, and which rooms are opened to it, and as such it can work out if the air should flow out of the room, or into the room. My though was to have each room act as a provider. So it would only handle airflow out of the room (as such each rooms airflow in would be handled by either a provider such as an air vent, or by other rooms)

The only issue I can see with this approach is that each room would have it's own script for managing this and as such tweaking things such as flow rate could become a pain. Is this something that should be more of a singleton that handles the airflow for all rooms. Or do i have the right idea making each room manage it's own airflow?

Hopefully I've explained myself well enough. And i appreciate any suggestions.