By Jaclyn Krah Cichowicz, MA; Christopher Coffey, Ph.D.; and Jonathan Szalajda, MS
(Released 17 June 2019) In the course of preparing for an emergency you might decide to buy a pack of respirators from your local hardware store, thinking that they are ready to use out of the box. However, before you can rely on one of these devices to protect you, there are some important selection and use criteria to consider. Choosing and using a respirator is a process that, if done the right way, can help you prepare and protect your health in an emergency.
In a previous post, we discussed two of the three key factors to effective respiratory protection, those being effective filtration and getting a tight seal between the facepeice and your face. Before discussing the third key factor–proper respirator use–let’s talk about respirator selection.
Selecting the Right Respirator
Filtering facepiece respirators (FFRs) are the most common type of respirator used by the public during disasters and emergencies. Within this category, the most common type of FFR is an N95 respirator. The number 95 indicates that the respirator’s filter is able to remove at least 95 percent of airborne particulates in a test that simulates a “worst-case scenario” using the “most-penetrating” sized particles. Learn more about worst-case testing in this video from NIOSH, A Particle is a Particle.
N95 respirators are the most economical and readily-available choice. They protect against many respiratory hazards, from airborne particulates found in wildland fire smoke to flu viruses. They are a dependable option to keep in your emergency kit. However, they are not a solution for every airborne hazard. N95 respirators are ineffective against oil-based agents, such as some solvents, paints, and pesticides. For protection against oil-based agents, you would need a higher-level FFR, such as the P100.
It is also important to understand that FFRs do not protect you against gases, such as carbon monoxide. For that, you would need a reusable elastomeric, which is a more complex type of respirator that protects against gases, vapors, and/or particles. However, elastomerics must be equipped with the appropriate filters and/or cartridges for the hazard. For example, a combination organic vapor and P100 cartridge would provide protection against particulates, specific gases, and vapors.
If it sounds like things just got complicated, it’s because choosing a respirator can be a complex decision. The key thing to understand is that you have to know the hazard in order to choose the right respirator. There is no umbrella respirator at your local hardware store that will protect you from any and all hazards.
Proper Respirator Use
Once you have determined the type of respirator you need, choose a size that seals tightly against your face, fitting over your nose and under your chin. If you cannot get a close face seal, try a different model or size.
Fit testing is the best way to determine if the respirator fits you. In the US, and many other countries, government-approved respirators include instructions on how to check to ensure that the respirator is properly sealed against your face. This process is called a user seal check. Doing a user seal check every time you put on the respirator will give you the best fit possible and is an important part of proper respirator use.
Every NIOSH-approved respirator comes with manufacturer’s instructions. Because every respirator is slightly different, these instructions are always the best source of information for how to properly put on, wear, take off, and store your respirator. In addition, these instructions will specify limitations of use.
NIOSH has manufacturer’s donning instructions for nearly every model of filtering facepiece respirator at www.cdc.gov/niosh/npptl/topics/respirators/disp_part/.
Putting on (or donning) a Respirator[i]
Before putting on a respirator, first inspect it for damage. Do not use a respirator that appears damaged. Also, do not allow facial hair, hair, jewelry, glasses, clothing, or anything else to prevent proper placement or to come between your face and the respirator.
- Position the respirator in your hand with the nose pieces at your fingertips. (Most FFRs have a thin metal or plastic bar at the top of the device)
- Cup the respirator in your hand allowing the headbands to hang below your hand. Hold the respirator under your chin with the nosepiece up.
- The top strap (on single or double strap respirators) goes over and rests at the back of your head near the crown. The bottom strap is then positioned around the neck and below the ears. Do not crisscross the straps.
- Place your fingertips from both hands at the top of the nose clip. Slide down both sides of the strip to mold the nose area to the shape of your nose.
Checking the Seal [ii]
Do a user seal check to determine if you are properly wearing the respirator. A user seal check can either be a positive pressure or negative pressure check.
To do a positive pressure user seal check, exhale gently while blocking the paths for air to exit the facepiece. A check is successful when the facepiece is slightly pressurized before increased pressure causes outward leakage.
To do a negative pressure user seal check, inhale sharply while blocking the paths for air to enter the facepiece. A check is successful when the facepiece collapses slightly under the negative pressure that is created with this procedure.
You should perform a user seal check each time you put on the respirator; however, it only can be considered truly accurate when a respirator has already been successfully tested for fit upon the individual. Avoid touching the facepiece after completing the user seal check to avoid contaminating your hands with potentially harmful particles.
Taking off (or doffing) a Respirator
Do NOT TOUCH the front of the respirator! It may be contaminated.
Remove by pulling the bottom strap over the back of your head, followed by the top strap. Remember, do not touch the facepiece of the respirator.
Discard in waste container. Wash your hands thoroughly!
Important Considerations for Respirator use Outside of the Workplace
Public use of a respirator is not subject to the same regulations required of employers in workplaces. Even though wearing a respirator during an emergency might be the safest course of action, you will not have the benefits of formal training, fit testing, or medical evaluation. NIOSH studies have found that during public health emergencies, many respirator wearers do not properly put on or wear their device, which could lead to a lack of protection[iii].
One of the most critical components to proper respirator use is fit testing. As previously stated, OSHA (29 CFR 1910.134) requires an annual respirator fit test to ensure that users receive the expected level of protection when respirators are used in an occupational setting. A fit test verifies that a respirator is both comfortable and correctly fits the user.
The benefits of a fit test include better protection for the employee and verification that the employee is wearing a correctly-fitting model and size of respirator[iv]. Higher than expected levels of exposure to a contaminant may occur if the respirator has a poor face seal against the user’s skin, which can result in leakage. Without fit testing, it is impossible to know how well a respirator fits you.
Even without training or fit testing, a NIOSH-approved respirator will still provide higher levels of protection than a non-NIOSH-approved single-strap dust mask, a loose-fitting mask, or an improvised device, such as bandana or t-shirt. [v],[vi],[vii].
[i] NIOSH . How to Properly Put on and Take off a Disposable Respirator. Pittsburgh, PA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2010-131, http://www.cdc.gov/niosh/docs/2010-131/
[ii] NIOSH . Filtering out Confusion: Frequently Asked Questions about Respiratory Protection, User Seal Check. By Krah J., Shamblin M., and Shaffer R. Pittsburgh, PA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication 2018–130, https://doi.org/10.26616/NIOSHPUB2018130External
[iii] Cummings, K.J., Cox-Ganser, J., Riggs, M.A., Edwards, N. and Kreiss, K., 2007. Respirator donning in post-hurricane New Orleans. Emerging infectious diseases, 13(5), p.700.
[iv] Duling MG, Lawrence RB, Slaven JE, Coffey CC . Simulated workplace protection factors for half-facepiece respiratory protective devices. J Occup Environ Hyg. 4(6):420-431.
[v] Rengasamy S, Eimer B, Shaffer RE. Simple respiratory protection—evaluation of the filtration performance of cloth masks and common fabric materials against 20–1000 nm size particles. Annals Occup Hygiene. 2010; 54(7), pp.789-798.
[vi] Rengasamy, S., Miller, A., Eimer, B.C. and Shaffer, R.E., 2009. Filtration performance of FDA-cleared surgical masks. Journal of the International Society for Respiratory Protection, 26(1), p.54.
[vii] Rengasamy S, Eimer BC, Shaffer RE., 2008. Nanoparticle filtration performance of commercially available dust masks, Journal of the International Society for Respiratory Protection, 25, p. 27-41
Released by the Centers for Disease Control and Prevention. Click here for source.