What is an air-purifying respirator?
Air-purifying respirators (APRs) provide respiratory protection by removing contaminants in the air that you breathe. APRs do this by filtering out particulates from the atmosphere including:
- fibers, and
- other particles indentified in milligrams per cubic metre on a safety data sheet.
APRs can also remove gases and vapours by attaching the appropriate chemical cartridge. Read our Respiratory Protection 101 post to learn more.
APRS come in two common styles:
- half-mask: Half-mask respirators have a rubber or silicone face seal that fits over the nose and under the chin.
- Full facepiece: Full facepiece respirators are fitted with filters or cartridges that purify the air as the user breathes.
Air-Purifying Half-Mask Respirators:
Half-mask APRs are relatively lightweight and offer good protection from many airborne contaminants. These respirators provide comfort and safety for the user.
However, air-purifying respirators do have some limitations:
- They cannot be used for all types of airborne contaminants and are limited by the type and capacity of the filters or cartridges used.
- Protection factors are not as good as those provided by a full facepiece APRs
- They do not provide any eye or face protection.
- They cannot be used in oxygen-deficient atmospheres or in atmospheres that have high concentrations of contaminants.
Proper fit is essential and many factors may affect the face-to-facepiece seal. For isntance, people with facial hair cannot use APRs if the hair comes between the respirator seal and their skin.
Air-Purifying Full Facepiece Respirators
Air-purifying full facepiece respirators work on the same principle as half-mask respirators. The facepiece extends around the entire face to cover the eyes, nose, chin and mouth.
Some advantages of full facepiece respirators include the superior seal they provide, therefore offering more protection than half-mask air-purifying respirators.
They also protect the eyes and face from irritating vapours, mists and splashed chemicals.
Full facepiece respirators are heavier than half-masks and are often less comfortable for the user to wear.
Full facepiece air-purifying respirators cannot be used for all types of air contaminants and are limited by the type and capacity of the filters and cartridges used.
Eyeglass wearers must also ensure that temple bars do not interrupt their face-to-facepiece seal. If required, prescription eyewear inserts are available for most brands.
Full facepiece air-purifying respirators cannot be used in oxygen-deficient atmospheres or in atmospheres that have high concentrations of contaminants.
Breathing may become difficult because of the additional effort required to draw air through the purifying media.
Similar to that of the half-mask, full facepiece air-purifying respirators cannot be used by personnel with facial hair which comes between the respirator seal and the skin.Full facepiece respirators are used when a greater degree of respiratory protection is needed or when eye and face protection is desirable