Respiratory protection is not the first line of defense

It’s natural to think of respiratory protection as an automatic requirement when workers are exposed to airborne contaminants, but in the hierarchy of controls, it’s the last line of defense. Engineering and administrative controls must be considered first. If such controls are insufficient or infeasible, and workers are exposed to hazards at levels above OSHA’s permissible exposure limits (PELs), respiratory protection is required.

Evaluate the workplace

The first step is identifying and evaluating the respiratory hazards in the workplace. This includes air contaminants such as harmful dusts, fogs, fumes, mists, gases, smokes, sprays, or vapors. Think about tasks or processes where employee exposure may occur, such as using or manufacturing hazardous chemicals, handling biological agents, treating patients who have respiratory infections, welding, grain handling, and painting.   

Evaluation must include a reasonable estimate of employee exposures to respiratory hazards and an identification of the contaminant’s chemical state and physical form. Where the employer can’t identify or reasonably estimate the employee exposure, the atmosphere must be considered to be immediately dangerous to life or health (IDLH).

OSHA sets enforceable PELs (most of which are 8-hour time-weighted averages (TWA)) to protect workers against the health effects of exposure to hazardous substances, including limits on the airborne concentrations of hazardous chemicals in the air. Most of OSHA’s PELs for General Industry are contained in 1910.1000 – Air Contaminants and are listed by chemical name in Tables Z-1, Z-2, and Z-3. Others are found in 29 CFR 1910 Subpart Z, Toxic and Hazardous Substances, as individual regulations.

Consider engineering and administrative controls

Employers should prioritize eliminating the hazard. If this isn’t possible, engineering and administrative controls must be considered. Engineering controls reduce or prevent hazards from coming into contact with workers. This may include enclosure or confinement of the operation, general and local ventilation, and substitution of less toxic materials. Administrative controls establish work practices that reduce the frequency, duration, or intensity of exposure, such as rotating workers between hazardous tasks.

Provide respiratory protection

Respiratory protection must be provided to workers when engineering and administrative controls are not feasible or are insufficient to reduce harmful exposures. OSHA’s Respiratory Protection Standard at 1910.134 regulates the selection, storage, cleaning, and use of respirators in the workplace. Respirator selection and use can be complex, and different hazards require different respirators. The standard also includes provisions for:

• Developing a written respiratory protection program,
• Conducting evaluations of the workplace,
• Training employees on respiratory protection,
• Fit-testing employees regularly,
• Providing medical evaluations, and
• Retaining appropriate records.