respirators

Respirators are personal protective equipment designed to protect the wearer from inhaling hazardous substances. They work by filtering or supplying breathable air, and are worn over the nose and mouth with a secure seal. They differ from simple masks by providing a controlled barrier against specific particulates, gases, or vapors.

There are several types of respirators. Filtering facepiece respirators filter ambient air and are available in various classes such as N95, N99, or P100. Elastomeric respirators have reusable facepieces with replaceable filters or cartridges, available in half-face or full-face configurations. Powered air-purifying respirators use a battery-powered blower to pull air through filters. Supplied-air respirators and self-contained breathing apparatus provide a direct air supply and are used in higher-hazard environments.

Standards and certification vary by region. In the United States, respirators purposefully used for occupational safety are typically NIOSH-certified, with letters indicating oil resistance (N, R, P) and numerical efficiency for particulates (for example, N95 means at least 95% filtration under test conditions). In Europe, EN 149 classifies filtering respirators as FFP1, FFP2, and FFP3. For gases and vapors, cartridges or canisters with appropriate adsorbents are required, and performance is specified for different contaminants.

Fit and use are critical. Proper fit testing and seal checks help ensure effectiveness. Respirators must be selected for the hazard, properly sized, and used with compatible eye protection when needed. They are not a source of oxygen and are ineffective in oxygen-deficient atmospheres or in some highly toxic chemical environments without appropriate cartridges.

Maintenance involves cleaning and disinfection of reusable models, timely replacement of filters or cartridges, and proper storage. Limitations include reliance on user compliance, potential discomfort, and reduced protection if damaged, contaminated, or worn with facial hair or poor fit.