Rotgas

Rotgas is a general term for the various chemical weapons used by RAIs/Zeds to ward away non-infected. To call them chemical weapons might be an exaggeration, as their effects are comparable to stink bombs rather than, like, mustard gas. The exact ingredients vary, but it essentially uses the smell of rotting meat. Zeds are not bothered by this smell but do not find it particularly appetizing, while non-infected are repulsed by it, leading to nausea and vomiting if they linger about the area. More advanced, synthetic forms of rotgas cannot easily be filtered out by gas masks, but of course using oxygen tanks and completely covering the face renders it ineffective.
Rotgas can be mixed with irritants, but because the infected VNO is sensitive, then it essentially loses its ability to be used around Zeds. Assuming additional ingredients are not added, rotgas does not have long-lasting health effects beyond the damage vomiting can do to one's mouth and throat.

Access & Availability

Licentia's armed forces make use of rotgas and most infantry units are equipped with a few canisters of it. Most infected over the age of 16 who are about to leave a commune and risk attack by non-infected can have a request for rotgas granted, but it is regulated in communes with a significant population of non-infected such as Taqfleck so it doesn't become a nuisance.

Discovery

Rotgas has been used by infected since mid-2016, where it was first made by crudely mixing rotting meat and urine, then spraying the mixture as an aerosol or out of water cannons. Proper canisters were developed starting around early 2017 by members of Zero's faction of infected.