Respirators, Masks and Filter Types, Organized & Explained

Very Real Risks

Many respiratory diseases are almost exclusively caused by workplace exposures, including silicosis, asbestosis, byssinosis, and chronic beryllium disease.

• There are currently approximately 12,000 deaths each year in the UK due to occupational respiratory diseases, about two-thirds of which were due to asbestos-related diseases or COPD.
• In Ontario, COPD prevalence increased by almost 65% between 1996 and 2007, and individuals with COPD account for one-fifth to one-third of all health care services used. The impact on individuals and on society, owing to reduced productivity and increased demands on the health care system, is substantial.

Respiratory Protection

• Respirators protect workers by preventing exposures to harmful airborne chemical and biological agents.
• However, a respirator that is not used properly will fail to provide adequate protection, and may even cause certain hazardous conditions.

Types of Protection:

• Dust Masks
• Air-Purifying Respirators
• Atmosphere-Supplying Respirators

Types of Respirators

• Tight Fitting Respirators.

• Loose Fitting PAPR- (Powered Air Purifying Respirator)

Classes of Respirators

• Positive Pressure Respirator- When inhaling, the pressure inside the respirator is kept higher than outside the respirator.

• Negative Pressure Respirator- When inhaling, the pressure inside the respirator is less than outside the respirator.

Tight Fitting Respirators:

Half-Face Cartridge Respirator

• These can be used for protection against gases, vapors, or particulates.

• Cartridges contain a filtering and/or adsorbing media that removes contaminants from the air. Thus the type of cartridge is selected based on the anticipated contaminant(s) in the work environment.

• Cartridges attach to the respirator inlets, so air entering the face-piece is purified before it is inhaled by the respirator wearer.

• On the front of the mask is an exhalation outlet with a one-way valve that
allows air to leave the face-piece.

Full-Face Cartridge Respirator

Full face-piece respirators are used when a higher level of respiratory
protection is needed, or when protection of the eyes and face is important.

Examples:

1. Hazardous waste bulking, in which there may be high atmospheric concentrations of vapors

2. Jobs involving chemicals that are irritating to the eyes

3. Pesticide or herbicide spraying, where overspray may contact the eyes

4. Research animal care, where allergens can affect the eyes as well as the respiratory system.

• Like the simpler half-face respirator, full face-pieces have interchangeable cartridges that are selected on the basis of anticipated respiratory hazard(s)

Disposable Filtering Face-piece Respirators

• Filtering face-piece respirators are intended to protect against particles, although some models may contain an activated charcoal media to control odors or vapors; however, this type of respirator is not recommended if you have potential exposure to gases or vapors.

Oil-resistance is indicated by N, R, or P:

• “N” means that the respirator is not resistant to oil

• “R” is more resistant to oil

• “P” is most resistant, and is often considered “oil-proof”

N-95 is the minimum level of efficiency that is acceptable for protection against hazardous particulates:

• Respirators with greater filtration efficiency are available (e.g. N-97 and N-100, R-97 and R-100, P-97 and P-100)

• An N -, R-, or P-100 filter is also called a High-Efficiency Particulate Air (HEPA) filter because it is nearly 100% effective at filtering test particles

N-95 or higher disposable respirators are effective for hazard reduction when working with infectious agents:

• Greater levels of protection might be required for specific agents or protocols.

Eye and face protection can be worn with disposable filtering facepiece respirators:

• E.g. goggles and/or face shield worn with disposable respirator in Biosafety Level 3 facilities

“Canister” Respirators

Canisters are sometimes used instead of cartridges for gas and vapor respirators, because more sorbent material can fit in a canister

These tend to be heavier than cartridge-using APRs, and are not widely used in some countries

Loose Fitting PAPR Hood:

Powered Air Purifying Respirator Hood

PAPRs are useful for work environments where traditional full face-piece respirators are not acceptable.

Example: if the work environment is hot with high humidity the traditional full face-piece respirator might fog up.

Loose Fitting PAPR Helmet:

Powered Air Purifying Respirator Helmet

Air is circulated through the helmet to provide a cooling effect & reduces fog.

Positive Pressure Respirator

PAPR-Powered Air- Purifying Respirators- Cannot be used in IDLH atmospheres.

Atmosphere Supplying Respirators

Atmosphere Supplying Respirators can be used in atmospheres where the hazard is unknown or IDLH.