Mine Safety Appliances, or MSA, is a maker of sophisticated safety products that help protect workers who may be exposed to a variety of hazardous conditions. The company’s product line includes gas monitoring and detection instruments, filter-type respirators, gas masks, breathing apparatus used by firefighters, thermal imaging cameras, firefighter helmets, ballistic body armor, military communications systems, a broad range of industrial head and fall protection products, and safety products for Do-It-Yourself consumers.