Selecting the Right Respirator for the Hazard
Article originally appeared in the Summer 2020 issue of VPPPA's Leader magazine.
By: Lynn Feiner, Sr. Offering Manager for Air-Purifying and SCBA Respiratory Protection, Honeywell
Recently there has been an increased demand for personal protective equipment (PPE) in nontraditional areas, such as office environments, retail establishments and airline travel. Use of PPE in new industries engenders a need for education on the proper use of PPE. Honeywell offers convenient digital apps to help individuals understand the correct ways to wear, use and discard PPE.
Today, we are focusing on choosing the right respirator for the hazard or contaminant, which will go a long way toward protecting workers’ health. According to the National Institute for Occupational Safety and Health (NIOSH), the basic purpose of any respirator is simply to protect the respiratory system from inhalation of hazardous atmospheres. NIOSH is the organization that provides guidance about respirator research, certification and training. They even created a helpful Guide to Industrial Respiratory Protection. The goal of their certification program is to help increase worker protection from airborne contaminants by certifying respirators that meet the minimum performance requirements based on federal regulations.
Please note that the occupational use of respirators should follow a written respiratory protection program and meet all local government regulations. In the United States, employers must comply with OSHA 29CFR1910.134 and in Canada, the respiratory program must meet the respective Province’s regulations, including compliance with CSA Standard Z94.4, if required. All workers should familiarize themselves with the required respirators and additional personal protective equipment appropriate for their worksites.
All programs should include evaluation, training and fit testing. Workers should have the opportunity to handle the facepiece or respirator, learn how to inspect it, don and doff, have it properly fitted, wear it in a normal air environment, and finally, wear it in a test atmosphere.
Choosing the Correct Respirator
Before selecting a respirator, there are several factors to consider. First, we need to determine the hazard or contaminant. Contaminants can take the form of particulates, gases or vapors:
- Particulates include dusts, mists and fumes
- Gases include acid gases like chlorine, and other gases such as ammonia
- Vapors include organic vapors and mercury vapor
Next, determine the concentration level of the contaminant. How much of the contaminant is in the work area and will the work area be open or enclosed?
Then determine how long the respirator will need to be worn. Is it just for a few hours at a time or will it need to be worn for 8 hours or more each day?
Finally, determine if there is a need for higher protection based on the nature of the hazard or contaminant.
NIOSH tests and certifies respirators based on their physical and performance characteristics, including filtration efficiency. Filters are rated according to whether, and how quickly, they degrade when exposed to oil-based aerosols or whether they do not degrade. The rating has both a letter and a number.
- N: Not for use with oil-based aerosols, degrades quickly.
- R: Restricted use. Change after 1 shift as it starts to degrade.
- P: Oil Proof, does not degrade when exposed to oil-based aerosols.
- Number: Particulate filters are rated 95, 99 or 100, which corresponds to the percentage of one micrometer particles removed by the filter. A 95 rating means that the filter removes 95% of particles of that size from the air. Filters rated 100 offer 99.97% efficiency and are considered High-Efficiency (HE or HEPA) filters.
Bear in mind, NIOSH-certified respirators may not function as intended if the respirator is modified in any way, and such modifications can result in serious injury, illness or death. Modifications will also void the NIOSH certification and warranties.
The simplest form of face covering is the surgical mask, generally made of three layers of spun-bond material or fabric. They're resistant to droplets such as those caused by coughing or sneezing and are typically used as a barrier for any particles the wearer may expel. These surgical masks are unable to prevent you from breathing in very small viral particles. Most surgical masks are not NIOSH certified respirators. Those that are NIOSH certified are known as surgical N95 respirators.
Respirators used when working with airborne particles or in healthcare settings are designed to fit tightly to the face to prevent inward leakage and require a rigorous fitting process. These respirators should be selected according to the efficiency of respirator filters in filtering aerosols, and according to the type of procedure to be carried out.
N95 filtering facepiece respirators, also known as disposables, have become a popular choice for use by healthcare workers in contact with patients with infections that can be transmitted through airborne droplets. When working with airborne particles, we recommend checking with your supervisor, facility, Occupational Safety and Health Administration (OSHA) and the Centers for Disease Control and Prevention (CDC) guidelines before beginning work. N95 respirators typically are not tested or certified as offering protection against pathogens or viruses such as COVID-19.
Elastomeric respirators, such as half facepiece or full facepiece, are tight-fitting respirators where the facepieces are made of thermal elastomers or silicone. These can be used repeatedly, cleaned, disinfected, stored and re-used, according to the CDC.2 It is important to note that the FDA does require fluid resistance or other ASTM testing of elastomeric respirators.
The half-facepiece is a tight-fitting, air-purifying respirator covering the nose and mouth while the full-facepiece respirator covers the user’s nose, mouth, eyes and face, offering additional protection. Elastomeric respirators may also have sealing surfaces and adjustable straps that accommodate a better fit.
Powered Air-Purifying Respirators (PAPRS)
Powered Air Purifying Respirators (PAPRS) are used when higher respiratory protection is required, to defend industrial workers and emergency responders from particulates such as silica dust, bacteria, mold spores and heavy dust. PAPRS are a type of air-purifying respirator that use a battery-operated motor blower to pull ambient air through an air-purifying element to the inlet covering. Simply put, the system uses a blower instead of lung power to draw air through the filter. This allows the user to breathe comfortably with less resistance, as the airflow is delivered directly into the headgear from the blower.
Although there may be a higher capital expenditure when choosing to implement PAPRs into an employer’s respiratory protection program, this expense may be justified since PAPRs may:
- Reduce the need for fit testing if used with loose-fitting facepieces, hoods or helmets
- Increase comfort to the wearer
- Integrate multiple types of PPE into one NIOSH-approved system (head, eye, face and respiratory protection)
Supplied Air Respirators
Supplied-Air Respirator Systems (SARs) utilize air from an external air source that is independent of the hazardous environment. The basic SAR is comprised of a respirator facepiece—which could be a tight-fitting half mask or full-face mask, or a loose-fitting hood or helmet assembly—connected via an air supply hose to a source of breathing air.1
Basic SARs are most commonly used in either one of two modes: continuous flow (the breathing air flows into the facepiece at a standard, steady rate) or pressure demand (the facepiece is continually pressurized with breathing air, and additional air is drawn in based upon the wearer’s breathing requirements). Pressure demand SARs require a high-pressure supply source due to their performance requirements. A high-pressure supply source would be either a cylinder or “cascaded” cylinders of breathing air, or the compressed air supply within a facility as long as it is filtered and monitored to ensure it meets OSHA’s purity requirements for breathing air.1
In addition to finding the right respirator for the hazard, you should think about comfort, fit and price. Disposable respirators that include an adjustable nose clip offer a better fit for more facial sizes and types. Disposables with an exhalation valve will be cooler and minimize the build-up of carbon dioxide inside the mask.
Any time you are working with or around hazardous materials that require a respirator remember to practice these safety tips:
Change filter: Filters should be changed when:
- Breathing becomes difficult
- The filter is getting clogged with the particulates
- Gas and vapor cartridges should be changed based on a site-specific change out schedule
Keep Dry: Filters and cartridges become ineffective when they get wet. This is also true for disposable respirators.
Discard: Throw away any broken or dirty/damaged respirators or replace the damaged parts. For instance, Elastomeric masks are designed to be repaired, not tossed.
Lastly, as the need for PPE for use in public spaces increases, choosing the right mask for the hazard couldn’t be more important. Workers should speak with their supervisors and safety managers about specific respirators, their employer’s written respiratory protection program and additional worksite requirements.
With the increase in demand for respirators, Honeywell has increased production of N95 respirators at multiple facilities and has developed convenient safety packs for use when traveling by air. The kits, which come in sealed packets, contain gloves, masks and wipes and are designed to better protect airline passengers and crew while flying.
Health and safety is the top priority when anyone is working with or around hazardous materials. Evaluating and understanding the nature of the hazard, its concentration level and the necessary duration of wear helps the user choose the right respirator.
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