Respirators

What is a respirator?

A respirator (for example, an N95 or higher filtering facepiece respirator) is designed to protect you from breathing in very small particles, which might contain viruses or particles of metal, glass, wood. These types of respirators fit tightly to the face so that most air is inhaled through the filter material. To work most effectively, N95 respirators must be specially fitted for each person who wears one (this is called "fit-testing"� and is usually done in a workplace where respirators are used). N95 respirators are most commonly used in construction and other jobs that involve dust and small particles.

Respirators protect the user in two basic ways.

• The first is by the removal of contaminants from the air. Respirators of this type include particulate respirators, which filter out airborne particles; and "gas masks" which filter out chemicals and gases. Other respirators protect by supplying clean respirable air from another source. Respirators that fall into this category include airline respirators, which use compressed air from a remote source; and self-contained breathing apparatus (SCBA), which include their own air supply.
• Respiratory protection is effective only if:
  • the correct respirator is used
  • it's available when you need it
  • you know when and how to put it on and take it off
• you have stored it and kept it in working order in accordance with the manufacturer's instructions

Particulate respirators are the simplest, least expensive, and least protective of the respirator types available. These respirators only protect against particles. They do not protect against chemicals, gases, or vapors, and are intended only for low hazard levels.

Chemical Cartridge/Gas Mask respirator. Gas masks are also known as "air-purifying respirators" because they filter or clean chemical gases and possibly particles out of the air as you breathe. This respirator includes a facepiece or mask, and a filter/cartridge (if the filter is in a metal shell it is called a "canister"). Straps secure the facepiece to the head. The cartridge may have a filter to remove particles (such as a biological weapon), charcoal (to remove certain chemicals), both, or other parts. When the user inhales, air is pulled through the filter.

Gas Masks are effective only if used with the correct cartridge or filter (these terms are often used interchangeably) for a particular biological or chemical substance. Selecting the proper filter can be a complicated process. There are cartridges available that protect against more than one hazard, but there is no "all-in-one" filter that protects against all substances. You need to know what hazards you will face in order to be certain you are choosing the right filters.