Breathe. Now think about the air you just inhaled and exhaled. You probably wouldn’t last long without it, would you?

Most people take clean, breathable air for granted. In many potentially hazardous work settings, however, respirable air is a precious—and federally regulated—resource. In order to protect people from smoke, dust, gases, sprays, low-oxygen environments, and other airborne risks, the Occupational Health and Safety Administration requires millions of workers to wear respirators. According to OSHA, compliance with these rules “could avert hundreds of deaths and thousands of illnesses annually.”

Can you breathe easy about your organization’s OSHA compliance, or is your respiratory protection program just hot air? Make sure you’re abiding by the following best practices:

1. Know Which Respirators Your Workers Are Required to Wear

Not all respirators are the same. OSHA has different requirements for different kinds of working environments, based on the hazards present in those environments.

There are two general kinds of respirators: air-purifying and atmosphere-supplying. According to OSHA:

“Air-purifying respirators use filters or sorbents to remove harmful substances from the air. They range from simple disposable masks to sophisticated devices. They do not supply oxygen and must not be used in oxygen-deficient atmospheres or in other atmospheres that are immediately dangerous to life or health (IDLH).

Atmosphere-supplying respirators are designed to provide breathable air from a clean air source other than the surrounding contaminated work atmosphere. They include supplied-air respirators (SARs) and self-contained breathing apparatus (SCBA) units.”

Air-purifying and atmosphere-supplying respirators each have their own applications and limitations. The former, for instance, is best used on a short-term basis, while the latter can be worn for extended periods of time. In either case, the respirator must fit properly and “must not impair the worker’s ability to see, hear, communicate, and move as necessary to perform the job safely.”

Additionally, every worker who wears a respirator must undergo a detailed medical evaluation by a physician or other licensed health care professional. Some workers may require follow-up evaluations based on their initial results, after reporting new symptoms, when working conditions change, or under other circumstances.

For more information about the different types of respirators, watch this video from OSHA. For more information about medical evaluations, read OSHA’s respirator standards.

2. Replace Respirators/Cartridges Before the End of Their Service Lives

You can’t use the same equipment indefinitely. Many respirators are equipped with end-of-service-life indicators (ESLIs) certified by the National Institute for Occupational Safety and Health. An ESLI tells you how long a cartridge or respirator can be exposed to certain contaminants before it needs to be replaced. Be sure to replace any cartridges or respirators before they expire.

If a respirator does not have a NIOSH-supplied ESLI, it’s your responsibility to implement “a change schedule for canisters and cartridges that is based on objective information or data that will ensure that canisters and cartridges are changed before the end of their service life.” You can do this by conducting experimental tests, using a math model, or going with the manufacturer’s recommendation. Each approach has its pros and cons. Whatever method you choose, you’ll need to be able to explain your change-out schedule, what data you’re using, and why you rely on that data.

For more information and guidance, see OSHA’s Respirator Change Schedules eTool.

3. Document Everything

In addition to your change-out schedule, you will need to document and maintain records on all respirators, fit tests, and workers’ medical evaluations. This information must be complete, up-to-date, and readily available.