MSA All-Service Gas Mask

This is the next generation of breathing apparatus. It utilized a chemical canister that would be inserted and punctured to cause a chemical reaction that would convert carbon monoxide to oxygen. In most fire departments, these "chem-ox" devices were replaced by self-contained breathing apparatus (using compressed air) in the 1950s and 1960s. However, the U.S. Navy was still using chem-ox breathing apparatus on aircraft carriers and other ships as late as 1998.