Thanks @baconandcoconut - you can see the pic of what I assume is the air filter mentioned in the legal and policy room in the FOSDEM2024 in the post below.
It also contains a link to some useful guidance on how much air you'd need to move to effectively clean the air in a room of the size of the policy dev room.
Can you expand on “Conservancy staff” I don't know what that is.
https://rtl.chrisadams.me.uk/2024/12/whats-the-air-quality-like-in-rooms-at-fosdem/
/cc @karen