In the mid 1980s there was a fire in a feed and fertilizer store in the city in which Glenn was living. Large quantities of smoke were generated and police were called in to assist with cordoning off and securing the area. Many of the officers who were stationed downwind ended up with some significant symptoms of chemical exposure through inhalation of the smoke from these agricultural products. Some people in the fire service used to good-naturedly refer to these perimeter officers as the “blue canaries,” demonstrating the boundary where use of respiratory protection was needed. Shortly after this fire, Glenn was asked to come help set up a respiratory protection program for the police department. To the best of his knowledge, the department didn’t have a single functional respirator available at the time of the fire.

Things have come a long way since then and use of respiratory protection in hazardous atmospheres is the norm. Yet there are still many misunderstandings and misconceptions surrounding the use of respiratory protection whether it is in response to a possible weapons of mass destruction incident, processing a crime scene with chemicals (yours or those on-scene), in confined spaces, or dealing with infectious agents. So let’s start at the beginning.

First, where respirators must be used to protect one’s health against respiratory hazards, OSHA requires development of a respiratory protection program in accordance with 29 CFR 1910.134. Where respirators are used in a voluntary fashion, some program elements may be required to prevent hazards associated with respirator misuse. Suffice it to say, if your organization is using respirators, there should be a written program and an administrator well versed in this OSHA standard.

Respirators are designed to prevent contaminated air from entering the body. There are several basic face piece designs. Typically one sees “half mask” respirators which cover just the nose and mouth, “full face piece” respirators which cover the entire face, and “hood” or “helmet” style respirators which cover the entire head.

Respirators can protect the user in two basic ways. The first is by the cleaning “dirty” outside air that passes through a filter or adsorption bed or both when one inhales. This type is known an “air-purifying respirator” (APR). The other main type of respirator protects the user by supplying clean breathing air from a remote source. The clean air can either be delivered via a supply line (supplied air respirators [SARs]) or the clean air is packaged and carried with you in a tank (self contained breathing apparatus [SCBA]) like a scuba diver.