High Quality Content by WIKIPEDIA articles! A hazmat suit is a garment worn as protection from hazardous materials or substances. A hazmat suit is generally combined with breathing apparatus for protection and may be used by firefighters, emergency personnel responding to toxic spills, researchers, specialists cleaning up contaminated facilities, or workers in toxic environments. It is sometimes confused with, or referred to as, an NBC (nuclear, biological, and chemical) suit, which is a military version intended to be usable in combat.