The odor is extremely pungent and you must use adequate ventilation and air circulation while in use. Under certain conditions, without adequate ventilation, air circulation, and the extinguishing of all flames in the area, they can create an atmosphere that will be corrosive to metallic surfaces throughout a home or structure. When used over existing vinyl floors, they can cause a migration of plasticizers between the vinyl floor and the mastic, that will not permit the mastic to set up. This problem is avoided by using primers designed to provide a barrier between the mastic and the vinyl floor, as well as an improved bonding surface. Incidentally, this is not peculiar to only chlorinated mastics.
Migration can also occur with emulsion formulations over vinyl.
At the present time, chlorinated mastics are the most widely used in the industry and will continue to be for the immediate future. The basic technology is already in place and being used. After all, we are already doing this with the PVA emulsion products on finger block installations. Keep a floor down forever under normal conditions. Fast and easy to complete the jobs.