Respirator air-purifying

Class B—Non-IDLH based on oxygen level between 19.5 and 21 percent, but classified as dangerous due to the airborne presence of toxic or poisonous substance Below IDLH level, but greater than the protection factor offered by air-purifying respirators. 

Figure 9-14 shows a typieal full-faee air purifying respirator (FF APR) with eartridges attaehed. Figure 9-15 shows what a worker donning modified level C proteetion (diseussed earlier in this ehapter) might look like. 

Figure 9-18 shows what the respirator looks like when assembled and ready to use. Figure 9-19 shows the eomponents of a powered air purifying respirator (PAPR). A typieal PAPR system uses a small fan to... 

FIGURE 9-19. Typical components of a powered air purifying respirator. Photo Courtesy 3M... 

Air-purifying respirator A respirator that removes airborne contaminants, such as particulates, gases, vapors and fumes, from ambient air through filtration, absorption, adsorption, or chemical reactions on the media contained in the cartridge or filter. 

Powered air-purifying respirator (PAPR) A type of air-purifying respirator that utilizes a battery-powered fan to draw contaminated air through the cartridge or filter into the facepiece. 

Use positive pressure air line with mask or self-contained breathing apparatus for exposure limits and emergency use. Air purifying respirators may not afford an adequate level of protection. 

Use a self-contained breathing apparatus (SCBA). Air purifying respirators (APRs) are not recommended for use in an arsine atmosphere because of poor warning properties and the unknown effectiveness of sorbents used in the filters. 

Metal carbonyls decompose in light to produce carbon monoxide. They are incompatible with strong oxidizers and readily form explosive mixtures with air. Some decompose at ordinary temperatures in contact with porous materials [e.g., activated carbon used in air purifying respirator (APR) filters] and produce carbon monoxide. 

Self-contained breathing apparatuses (SCBAs) or air purifying respirators (APRs) should have a National Institute for Occupational Safety and Health (NIOSH) and Chemical/Biological/Radiological/Nuclear (CBRN) certification. However, during emergency... 

MSA Home Page 2000, Air-purifying Respirators, Conventionally Maintained, Dustfoe Respirator (Pittsburgh, PA MSA International). 

Level C protection should be selected when the type of airborne substance(s) is known, concentration is measured, criteria for using air-purifying respirators are met, and skin and eye exposure are unlikely. It involves a full face piece, air-purifying, canister-equipped respirator and chemical-resistant clothing. This level of protection provides the same degree of skin protection as Level B, but a lower level of respiratory protection. 

Responders may use full facepiece respirator with a P100 filter or powered air-purifying respirator (PAPR) with high efficiency particulate air (HEPA) filters when it can be determined that ... 

Full facepiece, chemical canister, air purifying respirators. (The M9, M17 or M40 series or other certified equivalent masks are acceptable for this purpose in conjunction with the M3 toxicological agent protective (TAP) suit for dermal protection.)... 

Personal protective equipment is clothing and/or respiratory equipment worn to protect the body against various forms of contamination. Some of the most common forms of personal protective equipment include dust masks, air purifying respirators, protective suits made from particulates or chemically resistant materials such as Tyvek (E.I. Du Pont de Nemours Company, Inc., Wilmington, DE) and/or other fabrics, and lightweight protective rubber gloves or chemical-resistant gloves. 

Two examples of air purifying respirators are the MSA Ultra-Twin full-face respirator (Mine Safety Appliances Company [MSA], Pittsburgh, PA), and the 3M Model 6800 full-face mask (3M, St. Paul, MN). Figure 6.7 shows an air-purifying respirator. 

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