What is an air purifying respirator (APRs)?

Answer: A — a respirator with an air-purifying filter, cartridge, or canister that removes contaminants from ambient air

Air-purifying respirators clean the air you breathe by pulling ambient air through a filter, cartridge, or canister that removes contaminants before you inhale. They do not supply their own air; their effectiveness depends on the surrounding environment and the filter’s ability to remove the specific pollutants. That’s why the best description is a respirator with an air-purifying filter, cartridge, or canister that removes contaminants from ambient air. In contrast, atmosphere-supplying respirators bring air from a separate source (like a supplied-air line or a scuba-style tank), and a self-contained breathing apparatus is a type of atmosphere-supplying respirator with its own onboard air. The idea of purifying ambient air by passing it through a filter is on the right track but is not the defining classification; APRs are defined by having an air-purifying element (filter, cartridge, or canister) that removes contaminants from the surrounding air.