Air-purifying respirator cartridges and filters are installed in reusable half-mask or full-facepiece respirators to provide protection from airborne contaminants. Products are designed to protect against a variety of individual contaminants or combinations of contaminants, including dusts, particles, mists, aerosols, fumes, gases, and/or vapors.

Some products protect against both particulate and gaseous contaminants, however, there is no single filter and cartridge combination that protects against all substances.

Correct product selection depends on the environment(s) in which the product will be used and the type(s) of hazard(s) or risk(s) expected in the selected environment(s). NIOSH-rated cartridges and canisters use a color-coding system for secondary identification.

Product service life depends on many factors, including environmental conditions, breathing rate, cartridge filtering capacity, and the quantity of contaminants in the air. Regulatory compliance details for each filter and filter/cartridge package can be obtained at the individual product level and should be carefully scrutinized during selection.