Effects that Gas Masks protect against?

By Terraneaux, in Only War Rules Questions

Are there any actual printed game effects that these help against? I don't recall seeing choke or knock-out grenades in any of the official books.

"Respirators and sealed armour provide a +20 bonus to this Test." From the section on weapons with the Hallucinogenic quality, pg.170 Core Rulebook.

MY players had to enter a Hab Structure that had been infected with a bio hazard. They had to spend all their time in their gas masks.

Basically they are there to help with whatever poisons you come up with. Maybe the very atmosphere is toxic and the Respirators are needed for venturing out onto the surface.

Sooooo in short No there is nothing in the official books that would require you to be wearing a gas mask (although I would give it to them against Hallucinogen Grenades)