To get the best protection from a respirator, you need to learn about its different parts. When used, maintained, and replaced correctly, the different parts of a respirator can lessen your exposure to nearby hazards.
Filtering out the Hazards
Cartridges trap gases and vapors. Filters trap particles. All cartridges, filters, and prefilters must be certified by NIOSH (National Institute for Occupational Safety and Health). NIOSH rates filters on a scale of 3 efficiency levels: 95 percent, 99 percent, and 99.97 percent. Within these efficiency levels are 3 filter types:
N filters: These are used when no oily particles are present.
R filters: These can be used to protect against oily particles.
P filters: These provide the highest level of protection against all particles.
When to Replace Filters and Cartridges
Follow instructions from your supervisor or the respirator manufacturer to learn when to replace your prefilter, filter, or cartridge. As a rule, replace if breathing has become more difficult. Also replace as soon as you notice odors.