The Occupational Safety and Health Administration (OSHA) estimates that 5 million U.S. workers are required to wear respirators. For linemen and wiremen, respirators protect against environments with insufficient oxygen levels, harmful airborne dusts, fogs, smokes, mists, gases, vapors and sprays. Without respiratory protection, these hazards can result in serious health conditions, such as cancer, lung impairment, diseases or even death.
According to OSHA’s Respiratory Protection Regulation (1910.134): “The primary objective shall be to prevent atmospheric contamination. This shall be accomplished as far as feasible by accepted engineering control measures (for example, enclosure or confinement of the operation, general and local ventilation, and substitution of less toxic materials).” If engineering controls cannot eliminate the hazard, employees are required to wear appropriate respirators. Under these circumstances, employers must provide respirators to each employee.
Respirators either remove contaminants from the air or provide clean, respirable air from another source. The type of personal protective equipment (PPE) that removes contaminants from the air is known as a particulate respirator. It can filter out airborne particles, and it can have cartridges or canisters that filter out chemicals and gases. The other basic type is an airline respirator, which uses compressed air from a remote source and self-contained breathing apparatus (SCBA) with its own air supply to protect against respirable hazards.
When selecting a respirator, consider a number of factors. First, an employer should conduct an exposure assessment to determine the type of airborne hazard that workers will be subject to. The three basic types of airborne exposure hazards are chemical, biological and particle. Once the hazard has been identified, the employer should determine whether OSHA has established permissible exposure limits for that substance, be it asbestos, lead, crystalline silica, etc.
The next factor to evaluate is the physical environment in which the employee will be working. Some tight or confined areas may not allow the use of SCBAs. Similarly, working around obstructions or moving machinery that can snag hoses may limit the use of certain respirators.
Employers must consider the effect or burden that the PPE will have on the wearer. If an employee has a medical condition with restricted breathing symptoms, negative pressure respirators cannot be used. Likewise, when the respirator poses excessive physical burdens on the wearer, it should not be used.
According to OSHA’s Respirator Selection guidelines, worker preferences should be considered. “Among air purifying respirators, powered air purifying helmets have been subjectively rated the best for breathing ease, skin comfort, and in-mask temperature and humidity while filtering face pieces rated high for lightness and convenience. Each, however, has its own drawbacks, and all these factors should be taken into account during selection.”
Having reviewed all of the factors, the final deliberation in selecting the proper respirator is known as the assigned protection factor (APF). The APF reflects the level of protection that a properly functioning respirator would be expected to provide to a population of properly fitted and trained users. For example, an APF of 10 means a user could expect to inhale no more than one-tenth of the airborne contaminant present. The OSHA table below out- lines the appropriate APFs for selecting a respirator.
Finally, once the appropriate respiratory protection is in place, it needs to be maintained and inspected. According to OSHA, all respirators that rely on a mask-to-face seal must be checked annually to determine whether the mask provides an acceptable fit.
Furthermore, OSHA’s fit test guidelines indicate: “The relative workplace exposure level determines what constitutes an acceptable fit and which fit test procedure is required. For negative pressure air purifying respirators, users may rely on either a qualitative or a quantitative fit test procedure for exposure levels less than 10 times the occupational exposure limit. Exposure levels greater than 10 times the occupational exposure limit must utilize a quantitative fit test procedure for these respirators. Fit testing of tight-fitting atmosphere-supplying respirators and tight-fitting powered air-purifying respirators shall be accomplished by performing quantitative or qualitative fit testing in the negative pressure mode.”