Frequency of Respirator Fit Testing

Posted on by Ed Fries and Ziqing Zhuang

man wearing respirator for fit testOver three million American workers are required to wear respirators to protect themselves from hazards in their workplace. Since the fit of the respirator to the user’s face affects the protection provided by the respirator, occupational safety and health professionals recommend fit assessment during the initial selection of a respirator model and at some periodicity as part of a respiratory protection program. In 1998, the Occupational Safety and Health Administration (OSHA) adopted new requirements for occupational respiratory protection programs requiring respirator users to receive training and pass a fit test before using a respirator, and annually thereafter (29 Code of Federal Regulations Section 1910.134), based on current ANSI standards and public comments citing workplace experience.

Fit testing is the only accepted way to determine if the respirator fits properly. Periodic testing is needed to ensure the fit continues to be acceptable. One position is that annual retesting of respirator fit is needed to detect, at an early stage, the percentage of respirator users whose respirators no longer fit them properly. Another perspective argues that fit testing should be required only when an employee switches to a different respirator or when a significant change occurs in an individual’s physical condition which may interfere with obtaining an adequate faceseal.

The current fit test requirements and their rationale were questioned at the 2004 Centers for Disease Control and Prevention Workshop on Respiratory Protection for Airborne Infectious Agents in Atlanta, Georgia where participants called for the quantification of the benefit and the scientific validity of annual fit testing. Participants questioned whether annual fit testing must be performed in the same entirety and manner as initial fit testing and asked if annual fit testing could be redesigned to only verify proper donning of the respirator and acceptability of fit. The workshop also highlighted the need to quantify the role of weight loss or gain on fit testing.

In the 2007 Institute of Medicine (IOM) report, Assessment of the NIOSH Head and Face Anthropometric Survey of U.S. Respirator Users, the IOM recommended that “NIOSH […] perform research to determine which facial features have the greatest impact on respiratory protection of face masks in the workplace, using quantitative measures.”

To address many of the questions surrounding the periodicity of respirator fit testing, NIOSH is proposing a first-of-its-kind study that will assess respirator fit and facial dimension changes as a function of time for a representative sample of subjects wearing filtering-facepiece respirators (see the study protocol). NIOSH will recruit 220 study participants (subjects) representative of the U.S. workforce and distributed across the 10 face size categories of face width and face length. For each participant, NIOSH will collect a set of 13 traditional face measurements, height, weight, and a scanned image using a Cyberware Model 3030 head scanner at the onset of the study and every six months thereafter for three years.

Subjects will be required to pass a respirator fit test for inclusion in the study. All participants will be retained in the study regardless of subsequent changes in fit. The rate at which respirator fit changes as a function of time will be determined. Possible relationships between physical changes and changes in respirator fit will also be investigated. Knowledge gained from this research will be used to formulate hypotheses for additional studies to further explore questions surrounding the periodicity of respirator fit testing.

Some further questions for consideration in the protocol include, but are not limited to, the following:

  • Should subject/respirator combinations be limited to only those which initially provide appropriate protection?
  • What, if any, additional information regarding change in fit over time would be obtained by including subjects fitted with multiple respirator models?
  • Should NIOSH ensure the fitted respirator models include all types (cup, duckbill, flatfold, etc.) of filtering facepiece respirator designs?

The study is currently in the early stages of development. We would appreciate input to further inform the research as we proceed. Please provide comments on the study and methodology through the NIOSH Science Blog before June 1, 2008. This study is part of the NPPTL Facial Anthropometrics Research Roadmap.


Mr. Ed Fries is an engineer in the NIOSH National Personal Protective Technology Laboratory (NPPTL) Office of the Director and serves as the Assistant Coordinator for the NIOSH PPT Program.

Dr. Ziqing Zhuang is a senior researcher in the Technology Research Branch at the NIOSH National Personal Protective Technology Laboratory.

Posted on by Ed Fries and Ziqing Zhuang

98 comments on “Frequency of Respirator Fit Testing”

Comments listed below are posted by individuals not associated with CDC, unless otherwise stated. These comments do not represent the official views of CDC, and CDC does not guarantee that any information posted by individuals on this site is correct, and disclaims any liability for any loss or damage resulting from reliance on any such information. Read more about our comment policy ».

    All types of filtering facepieces should be included. There are potential for shortages in one type or another should demand increase.

    It would be of interest to see the frequency of facial changes over time and whether this results in a need for a change in mask shape/design as well as size.

    It would interesting to see if subjects fitted wih each currently available design types at the outside, change in fit characteristics over time.

    It would also be interesting to see if fit is maintained during actual work performance for HCWs. Too bad there wasn’t a ‘dosimeter’ type device that could measure this!

    Thank you for your comment. Unfortunately, it is not possible at this time to include all types of filtering facepieces. We anticipate that human subject data will be collected almost daily to enable us to gather the data required to conduct the analysis from all participant/respirator models already planned. Our human and fiscal resource constraints do not provide us the ability to conduct an expanded version of this study at this time. Please see the response to Myra Badger concerning our hope that other interested researchers will conduct similar studies to increase the scientific knowledge base available for analysis. We will provide our findings on the NIOSH web site at the end of the study.

    To determine if fit is maintained during actual work performance is a study which would require a different protocol and separate objectives. Researchers have published literature describing prior workplace protection factor studies undertaken to assess workplace protection provided by respirators.

    Thank you for your comment. There are some constraints with the study we are proposing. The NIOSH study is limited to using human subjects in the Western Pennsylvania region due to the cost prohibitive nature of traveling to collect the data. Although collection of data for each subject will only be required on a 6-month frequency, we anticipate that NIOSH will gather human subject data almost daily in order to obtain the necessary data from all 220 participants. Additionally, several visits to our facility will be necessary to complete the semi-annual collection of data for a subject. At this time, our human and fiscal resource constraints do not provide us the ability to conduct this study in locations outside a reasonable distance from our laboratories, since subjects will be required to travel to our location in order for us to collect the data.

    Our intent is to prepare our final protocol to enable other organizations in other areas of the U.S. and interested researchers to repeat our study and collect data similar to the data we intend to collect. We suggest that you share this protocol with your organization and solicit their willingness to conduct a study similar to the study outlined in the protocol. We intend to restructure the protocol to inform potential researchers what equipment will be necessary for each component of the protocol. We understand there may be equipment constraints which may limit the ability of researchers to repeat all aspects of the protocol. We also could provide opportunities to educate other research institutions on the facial measurement techniques to improve the likelihood of consistency. We encourage other researchers to consider other respirator types and styles in their studies to enhance the information shared at future meetings. If you are unable to participate in a study, we will provide our findings on the NIOSH web site at the end of the study.

    Thank you for proposing a study as this. For a while now this OSHA requirement has been a burden to our Fire/EMS service. This due to our minimum manpower and staffing for the size our department. As we struggle to keep up with this requirement due to such constraints; in reality it seems more fessible to support and have enforced the second position mentioned in this article (ie, re-fit testing on new respirators or changes in facial features) for a service like ours. Any help in reaching a more realistic compromise would be appreciated.

    Thank you for your comment. Through this study, NIOSH seeks to establish scientific evidence about how respirator fit is affected by changes in facial dimensions over time which will allows us to better understand the science of respirator fit.

    Thank you for comment. The NIOSH/NPPTL panel captures 97.7% of the US workforce and Asian facial sizes do fall within the 97.7% based on our study results.

    I would be interested in this study, we currently fit test our employees annually. If this process could be shortened or redesigned so that it was easier to do would help tremendously.

    Thank you for your comment and the interest in our study. Our intent is to prepare our final protocol to enable other organizations and researchers to repeat our study and collect data similar to the data we intend to collect, thereby enabling researchers worldwide to gather annually to discuss approaches and results. NIOSH has several goals in soliciting interest from other researchers to conduct this research: (1) to host annual teaching sessions on the science of respirator fit changes as a function of time for subjects wearing filtering-facepiece respirators, with lectures by leaders in the field; (2) to assess the current state of the field by applying current methods used to assess the science of respirator fit to an established research protocol and modifications which others may choose to incorporate and discuss the strengths and weaknesses of each approach; (3) to establish a consensus on minimal data requirements, common nomenclature, and objective methods for comparing performance across platforms and laboratories for respirator fit research; and most importantly (4) to establish a multi-laboratory, international working group dedicated to understanding respirator fit and providing scientific validation to regulatory requirements. Following the teaching sessions, each participating group could present their results, after applying their approach to accomplishing the objectives described in the protocol.

    See the response to Myra Badger for information regarding how your organization may conduct this or a similar study to provide input to the scientific knowledge base. If you are unable to participate, at the end of the study, we will provide our findings on the NIOSH web site.

    Workplace testing requirement for respirators are necessary to protect the health and safety of respirator users, in accordance with specific approved requirements, to give an assurance to the user that the equipment will afford the degree of protection required, to consider the man which is being required to wear the protective device as a human life that may be endangered: it comes a real need to harmonize standards according to an agreed physiological or subjective value.

    Thank you for your comment. NIOSH agrees and we are focusing on ways to develop sound scientific evidence from which to harmonize PPE standards.

    I would be interested in being part of this study on the law enforcement side. We fit test our officers annually but many departments do not. Law Enforcment traditionally has fallen down in this area as many agencies just give their officers their masks without any fit testing. We also fight the battle with our management with what is mandated. I, too would like to see all types of respirators tested. We have respirators from the N95 up to SCBA. All of our sworn officers have the Millenium APR and the N95. We fit test almost 500 yearly.

    I would be willing to participate. I wear a respirator for Fire investigation, and Hazmat type situations.

    Thank you for your comment. See the response to Myra Badger for information regarding how your organization may conduct this study to provide input to the scientific knowledge base. If you are unable to participate, at the end of the study, we will provide our findings on the NIOSH web site.

    Would the effect of body fluid discharge and subsequent drying while working with a respirator on facial skin and respirator seal be considered as part of this study?

    I would also be interested to know how tight is tight enough to prevent effects of talking and body fluids on the seal of respirators.

    Body fluid discharge, like sweating, and subsequent drying will not be part of our study; however, we encourage other researchers to adapt our protocol to explore these issues. The “talking” component of your question is part of the exercises in the OSHA respirator fit test protocol. To our knowledge the scientific evidence regarding “how tight is tight enough to prevent effects of talking and body fluids on the seal of the respirators” have not been subjects of a formal research study.

    I have worn respirators of all types and magnatudes from SCBA as a firefighter down to the half face APR. Working as a construction worker in almost all of the environmental fields. I am concerned that changing the fit test frequency while cost effective may defeat its overall purpose.

    when fit testing went from every 6 months to one year as a requirement of OSHA it was a step back.

    This last change on respirators and Protection Factors was also I feel a trade off. And needed to have more users of the respirators then the manufacturers.

    I would be very interested to take part in your study.

    thank you

    Thank you for your comment. NIOSH, through this study, is seeking to establish some scientific evidence about how respirator fit is affected by changes in facial dimensions over time to better understand the science of respirator fit. In this particular study we are examining only the N95FFR types. We are the honest broker of science for both the employer and employee and hope to provide sound evidence for use in making informed decisions about respirator fit testing.

    See the response to Myra Badger for information about participation in this study.

    As a career fire safety officer that started in the fire service before we had SCBA, and the increase incidents of cancer in firefighters, why would you not want to be fit tested every year? The gasket that meets the CBRN requirement is not as forgiving as the silicone units and any physical change in facial features could have a great effect on the wearer (positive pressure or not). If you do not have the proper seal, the amount of usable time in the SCBA will be greatly reduced and further put yourself and fellow firefighter in jeopardy. In the OSHA standard 1910.134 the burden is on the employer to provide you with the proper protection. Let’s not digress.

    Thank you for your comment. See the response to Kevin MacDonald.

    I am glad this study is being done. Respiratory fit testing is expensive for employers and it will be good to have a current answer when asked why we have to do the testing so often….or maybe not so often as the case may be.

    Thank you for your comment. NIOSH through this study is seeking to establish some scientific evidence about how respirator fit is affected by changes in facial dimensions over time to better understand the science of respirator fit. While the debate will likely continue after this study, our research will provide policy makers with sound evidence to help make informed decisions abut fit testing.

    I am a firefighter and an engineer. Overall, this study is a great idea and hopefully will spawn additional studies. I have to make a couple of comments based on the study as currently planned and the comments that others have posted.

    An interesting set of data that may come from this study are whether a certain face shape is more likely to fail the fit test than another face shape. This would assist the heath representative in recommending respirators. Secondarily, if a certain face shape will only pass the fit test with one respirator (out of the 15 types to be used) then the results may reflect more on the quality of that respirator than on changes in face shape.

    I believe the title of the study is misleading, especially to those in the emergency services (fire, rescue, police). The respirators used in the study appear to be displosable particulate respirators (“filtering facepiece respirators”) and the results of this study will have no direct relation to the SCBAs that are used in the emergency services. In fact, the protocol explicitly states that this study will not even include elastomeric facepieces. The response to the comment from Lt. Hernandez makes no mention of this fact.

    Although this study will contribute to the science of fit testing, the results will not be directly applicable to the annual SCBA fit testing required in the emergency services. This should be made clear to the emergency services providers commenting on the study.

    Thank you for your comments. First, the NIOSH respirator panel will be used for this study. Research demonstrates that 97.7% of the US workforce is captured with this panel, and we are looking for representative subjects who fall into the ten cells in that panel. As described in the protocol, subjects will be fit with one respirator which will be used throughout the duration of the study. Subjects will not be fit for all respirators used in the study. The respirator for a given subject will be randomly selected from those available for the study. If the subject fails to qualify with that model, another model will be randomly selected from the other’s that remain. One can not infer that the results of not passing the fit test reflect more on the quality of that respirator than on changes in face shape.

    We realize the NIOSH blog title is not as descriptive as the protocol title; however, the protocol is accessible to enable interested parties to understand the study. Filtering-facepiece respirators were selected for this initial study because: (1) many more workers use filtering-facepieces than use elastomeric half-masks; (2) the requirement for annual fit testing has been questioned by the health care industry – users of predominately filtering-facepieces; and (3) our resources and budget are limited. Our human and fiscal resource constraints do not provide us the ability to conduct an expanded version of this study at this time. If this study shows promise, then we might want to examine additional filtering facepiece respirators and/or SCBA in another study.

    Is the fit testing to be conducted by the Qualitative or Quantitative method? Our CSA Standard Z94.4-02 Selection, Use and Care Of Respirators, allows either one. The Standard also recommends annually, but requires every other year.

    Are the subjects allowed any facial hair (as long as it does not interfere with the seal of the respirator to the skin). I applaud you for your diligence and look forward to your results.

    Thanks for commenting on this topic. The protocol specifies a quantitative method using the Portacount Plus Model 8020A (with Companion accessory), manufactured by TSI, Inc., of St. Paul, MN following the procedure defined in OSHA’s respirator regulation 1910.134.

    The protocol complies with OSHA requirements regarding facial hair. Specifically, the protocol states that the test shall not be conducted if there is any hair growth between the skin and the facepiece sealing surface, such as stubble beard growth, beard, mustache or sideburns which cross the respirator sealing surface. Any type of apparel which interferes with a satisfactory fit shall be altered or removed.

    This looks like a potentially very productive study, thank you. I have a question about methods though, not of the anthropometric variety, but of the testing methodology.

    There is the NIOSH standard quantitative fit test, there is also the possibility of the Crutchfield RE-DON strategy, approved by OSHA to check facial seal under stress. Could your study use both methods, which would proceed to achieve your goal: and maybe provide a shorter re-test strategy, if it is found to be as safe a test of seal as the CDC – NIOSH 8-step standard test? Which would please the clinicians I test mightily.

    Thank you for your study.

    Thank you very much for your comment. The study at this time doesn’t employ the Crutchfield Re-Don strategy; however, we will examine the possibility of adding it to the study. The study does require the subject to demonstrate, through a series of nine donnings, that they can achieve adequate protection with high consistency. A subject will be considered to have demonstrated adequate protection with high consistency when, after nine trial donnings, the 90th percentile penetration is 0.05 or less.

    As a person who has done respirator fit testing since 1992 and done the annual fit testing of our company employees since 1998, it is my opinion that fit testing for filtering face pieces or more commonly called dust masks is strictly a subjective test. Because of that I have always felt that fit testing for dust masks should no longer be required.

    As for tight fitting respirators, of the 800 fit tests I’ve done over the past 10 years, you can count on one hand the number of employees who needed to replace their respirators because they failed their fit testing.

    Our agency provides surgical masks (for use by others); 3M 9010 individually wrapped, flat fold N95 disposable respirators; MSA Advantage 100 or 200 elastomeric half-mask respirators; and MSA Millennium full facepiece respirators to law enforcement personnel, forensic technicians, and other field personnel in the respiratory protection program. Forensic technicians use GME/P100 filters and all other use P100 filters on Advantage respirators. RCA and CBRN canisters are issued for Millennium gas masks. Corrections personnel are provided the same N95 respirators and surgical masks. Several teams, including SWAT, EOD, and the jail tactical unit, use Scott Air-Pak SCBA. Our program calls for all employees to be fit tested annually on all issued or approved respirators. Approximately 1,200 people are in the respiratory protection program.

    Few law enforcement employees see any logic in OSHA’s one-size-fits-all annual fit testing requirement, and some agencies have reduced the types of issued respirators to reduce the number of required fit tests. A well documented scientific basis for annual fit testing requirements will go a long way toward justifying the effort and expense.

    Universally-sized N95 respirators, such as 3M’s 9010, have given us an advantage over those that were more narrowly sized. They are easy to carry and keep clean. Every employee is passing fit testing with these respirators. Fit testing of half-mask and full facepiece respirators have occasionally resulted in the need to issue different sized respirators.

    Because we use respirators from the same company, it is rare to have someone need different sizes among different models. Physical changes that require a different size respirator have been obvious and would have resulted in fit testing even without an annual fit testing requirement.

    Law enforcement personnel generally carry respirators for airborne pathogens, riot control agents, and to provide protection and entry options with CBRN protection. SCBA is used by specialty teams. APR are rarely used, other than in training and for infection control (TB, Measles, Varicella, etc.). From a practical standpoint, fit testing has more value due to its ability to increase the level of confidence in the respirator’s ability to protect than it does in identifying subtle changes have occurred in facial features. Approval of the Abbreviated QLFT test is greatly anticipated as we expect it to provide the same level of protection while also instilling confidence for both employer and employee.

    NIOSH should include several models of universally-sized N95 respirators in its study, such as the 3M 9010, and determine if they should be excluded from annual fit testing requirements. NIOSH should also determine if there is a significant reduction if the effectiveness of flat fold N95s versus molded N95s. NIOSH should also determine if there is a scientific basis for identical fit testing requirements for workplaces where employees work all day in an environment that requires a respirator and for workplaces where a respirator may one day be needed.

    Note: References to product names do not constitute an endorsement of any commercial product by NIOSH or the U.S. government.

    Thank you for your comments on this study and your suggestions for enhancing the research. Input from PPE stakeholders who are users of PPE adds value to the success of the study. We will contact you to discuss your suggestions in more detail.

    MaryAnn Gruden, CRNP, MSN, NP-C, COHN-S/CM Coordinator, Employee Health Services The Western Pennsylvania Hospital Pittsburgh, PA says:

    As an occupational health nurse in healthcare, I am very pleased to see this study to address the issue of respirator fit testing frequency. This will provide the evidence on which we can make sound practice decisions. I work in a hospital in the Pittsburgh area and would be interested in discussing the possibility of our facility participating in the study.

    Thank you very much for the opportunity to comment on the study.

    Thank you for your comments. We are pleased to learn of your interest in this research study. We will contact you to discuss the possibility of your organization participating in our study.

    The Association of Occupational Health Professionals in Healthcare (AOHP) is pleased to see this proposed study and supports NIOSH’s efforts to study this issue. Our position has always been that the requirements for fit-testing, especially annual fit testing, be based on scientific evidence. We see this first-of-its-kind study as a significant step forward to gain evidence-based information for use in making future recommendations related to respirator fit testing. Thank you for the opportunity to comment on this study.

    Although understanding the requirements has be combursome, costly both in time and man power, I see to the need to effectivly reduce the burden to increase compliance.

    My concern fall on the inability to test each subjuect given it complexity. Example individuals with prosthetics and deformities in standard and non-standiaed environments

    I work in another field, so I’m investigating this issue: Our Police Swat Team uses 3M FR-C2A1 filters ….. My question is this… the OSHA respiratory program requirements apply to Police Departments, or are they exempt from this requirement of having policies, procedures, fit tests and medical evaluations? Thanks!

    Interesting study and discussion.

    I’m responding to Carol Buck’s question since it relates to jurisdiction, rather than the research. Local and state government public employers (including law enforcement) are exempt from OSHA in states where federal OSHA enforcemes directly (there are currently proposals before Congress that would change that if enacted). In states with approved state plans, however, the current federal law actually requires that local and state government be covered.

    So the answer to your question depends upon what state you live in. In addition, in some states that do not have state plans there may be state laws or guidelines that would apply even though the OSHAct itself does not.

    You can find the list of states with approved state programs at

    My company and I are responsible for providing fit testing services and respiratory protection equipment to a broad range of users such as but not limited to Academia, Construction, Environmental, Governmental, General Industry, Healthcare, Military, Mining, Public Safety (Police, Fire, Special Operations) and Utilities. In going on ten years worth of experience and many fit tests covering a wide array of makes, models and types as well as varying test subjects it is quite clear that some makes and models of respirators just plain fit a much broader range of users and face types better than others. Based on this experience I cannot help but wonder how you intend to correlate and/or remove the bias potentially created in the testing due to differences in overall respirator design, construction and material variances between the different manufacturer’s and models?

    I would also like to inquire why the study is using the TSI Portacount as the only analytical tool? The Controlled Negative Pressure (CNP) Technology from Occupational Health Dynamics (OHD) utilized in the Fittester 3000 and Quantifit is both widely used in the marketplace and is accepted by ANSI and OSHA. In addition to the test protocol taking considerably less time to perform unlike the technology used in the Portacount CNP is a direct measurement of leakage through the Controlled Negative Pressure as well as the volume of air required to be drawn to maintain the challenge pressure and therefore the fit afforded by the respirator.

    Thank you for the opportunity to comment on this valuable study.

    I need a publication in respirators and masks and specifically about FIT TESTING. Do you offer or sell any of such publications or can you suggest one for me?

    More information about fit testing can be found in the mandatory OSHA Fit Testing Procedures mentioned in the first paragraph of the blog. Please note that NIOSH does not recommend the Irritant Smoke Protocol (Part B, #5) listed in the OSHA Fit Testing Procedures. Additionally, the following OSHA website contains training materials for the OSHA respirator standard including a Power Point Presentation and Frequently Asked Questions:

    I have nineteen years experience in respirator fit testing utilizing the TSI model 8020. Currently I manage the OHS division of Houston Area Safety Council. Last year we performed 24,326 fit tests. I would be interested in sharing knowledge with NIOSH.

    Following September 11, 2001 assisted with medical clearance and respirator fit testing for workers at the former site of the World Trade Center.
    January – May 2004 Worked with New York City Police Department to assist in administering respirator fit tests to over 10,000 Police Officers.

    I am very much in favor of annual testing. Our hospital is so far out of compliance it is not funny. I was fit tested 12.5 years ago when hired and not since.Many nurses have not been fit tested for much longer than this.

    I am currently on Workers Comp with H1N1 exposure as are several of my coworkers.Now after bringing this to our employer’s attention as well as the requirement,they are attempting to comply with a haphazard program

    Do all respirators require fit testing. For example, I work in corrections. Currently we fit test are medical staff with the N95 1500 Series that comes in sizes S, Med, and Lrg. Our correctional staff and facility administration are preparing for H1N1 procedures. We have over 300 correctional staff. Do all staff members have to be fit tested or can a universal size mask be purchased?

    Is a fit test required for drivers at a DME co.? Very little time spent with pt’s.If pt has known TB or resp infection an N 95 mask is worn. Instructions state a fit test will not be done when mustache/beard present,what then is the reccomendation?

    Required respiratory protection is dependent on the exposure. When respirators are required in the workplace as part of an OSHA Respiratory Protection Program, a fit test is required to ensure maximum protection is provided by the respirator. As you correctly stated, OSHA Regulation 1910.134 states “A fit test shall not be conducted if there is any hair growth between the skin and the facepiece sealing surface, such as stubble beard growth, beard, mustache or sideburns which cross the respirator sealing surface.” In this situation there are two choices: 1) the individual should shave the hair growth to enable a fit test to be conducted, or 2) the individual should be issued a loose fitting Powered Air Purifying Respirator (PAPR) which does not require fit testing.

    I am new to repirator fit testing and will be required to do a series of fit testing. What type of catridge I should have users use wear using isoamyl acetate (banana oil) to conduct a fit test? There are lots of differnt ones – organic dust/fumes, acid, etc. I want to make sure I test using the right one. Thank you.

    Isoamyl acetate (banana oil) is an organic vapor (OV), so the test should be performed with a cartridge that includes OV as one of its listed protections. Further, your fit test should be conducted with the same part number cartridges you intend to use in your workplace to protect you from the potential exposure, assuming OV protection is included on the cartridge’s NIOSH approval label.


    On October 14, 2009 the CDC issued Interim Guidance on Infection Control measures for 2009 H1N1 Influenza in Healthcare Settings, Including Protection of Healthcare Personnel. The Guidance includes the following recommendation:

    CDC continues to recommend the use of respiratory protection that is at least as protective as a fit-tested disposable N95 respirator for healthcare personnel who are in close contact with patients with suspected or confirmed 2009 H1N1 influenza.

    The guidance document and Questions and Answers Regarding Respiratory Protection for Infection Control Measures for 2009 H1N1 Influenza among Healthcare Personnel provide the most updated guidance for healthcare personnel.

    On 10/14/09 NIOSH posted the blog N95 Respirators and Surgical Masks that examines the scientific principles behind the design and performance of surgical masks and respirators.

    Our hospital has seen a huge increase of patients with or the potential to have H1N1. Due to this, our stock pile of N95 masks are decreasing faster than we can resupply with the one particular manufacturer type. Our Materials Management can get another brand of the N95 mask but now there’s controversy if everyone will have to be re-fit tested again. The 2 mask are very similar other than one is a bit more rigid than the one we are currently using. My question then is do we need to re-fit everyone for this other manufacture’s N95- Thank you.

    Respirator models from different manufacturers do not have the same fitting characteristics, despite similar physical appearances. Any personnel using the replacement model respirator need to be trained and fit-tested for use of that model. Healthcare personnel conducting the highest exposure risk activities (i.e., aerosol-generating procedures) should only wear fit-tested N95 respirators. Using disposable N95 respirators that have not been fit tested does not provide the same assurance of respiratory protection as ones that are fit-tested because some individuals may have poor fit. Where a shortage of respirators exists despite reasonable efforts to obtain and maintain a sufficient supply for anticipated needs, in particular for very high exposure risk situations such as some aerosol-generating procedures, a facility should consider shifting to a prioritized respirator use mode. Your facility should also ensure that the number of exposed personnel is reduced to the minimum, in an effort to extend the time the original model of respirator remains available while persons are phased into the use of the replacement model.

    In the context of supply limitations during the current pandemic, non-fit-tested disposable N95 respirators can be considered for personnel at lower risk of exposure or lower risk of complications from influenza until fit testing can be completed. This use will provide protection from droplets and splatter, as would facemasks, but also will provide some additional protection against small particle aerosols. Personnel using the replacement, non-fit-tested disposable N95 respirators should receive training on use of the model being used. Facilities should fit-test workers with the new model of disposable N95 respirator as soon as possible, beginning with those staff who are assigned to duties that involve higher-risk exposure (refer to Table 2 in the CDC Interim Guidance on Infection Control Measures for 2009 H1N1 Influenza in Healthcare Settings, Including Protection of Healthcare Personnel for relative risks of different activities).

    Roland BerryAnn is the Deputy Director of the NIOSH National Personal Protective Technology Laboratory.

    As Roland says, Respirator models from different manufacturers do not have the same fitting characteristics.

    Add that with the fact that with the different facial features that Americans have it makes it difficult to find a decent fitting mask or respirator.

    Why not just add a seal to your respirator?

    We have been using the Breathe Safely seal. No more messing around leakage! It really is that simple. The seals provide an average of 270% more protection (according to their website). I don’t think that number really matters though. It either works or it doesn’t. You are protected or it is going to leak and usually they will leak.

    Please note:

    NIOSH has not evaluated the seals that are the subject of this comment as part of any respirator certification. Attachment of the seals to a NIOSH-approved respirator’s facepiece sealing surface is considered an unauthorized change to the respirator’s approved configuration. Therefore, using such seals voids a respirator’s certification.

    References to products or services do not constitute an endorsement by NIOSH or the U.S. government.

    I would like to be a part of the study. Wear respirator and have fit test annually, but is the respirator dangerous to the skin in any way ?

    My skin is very sensitive and i have acne, so i have been taking skin treatment so it would be terrible if my treatment would go wrong because of the respirator test.

    Thordur Runars

    My employer, a healthcare system, has ask me to participate in fit testing, but I have a lifelong history of asthma. I am particularly sensitive to inhaled irritants, including but not limited to cigarette smoke, many perfumes and even otherwise benign-appearing agents such as powdered sugar. I have declined fit testing due to health concerns about bronchospasm during the procedure, but I am willing to wear a respirator as required by my employer (as I have done, with an N95 respirator, in the past without adverse effect). Is there any medical waiver that would allow me to decline a potentially harmful fit test, but still fulfill my employer’s obligation to offer a mandatory fit testing?

    There are no medical waivers for fit testing when using tight-fitting respirators such as the N95 respirator. The test agents used in the OSHA-accepted fit tests are generally considered to be “benign” agents. Stannic chloride, which is used in the irritant smoke fit test, is not recommeded by NIOSH and is the exception. If you fear or have adverse reaction to the test aerosols due to the extreme sensitivity you describe, options for meeting the fit testing requirements are available to your employer that would avoid exposure to any test aerosols other than the ambient atmosphere.

    You should discuss the options that are available with the administrator of your employer’s Respiratory Protection Program. Examples of alternatives available to you and your employer are provided below:

    Your employer can conduct the fit testing with an OSHA-accepted quantitative fit test using ambient aerosol or controlled negative pressure. These fit test protocols can be performed without adding any type of inhaled aerosol, so there wouldn’t be any added irritants to cause an allergic reaction.

    Another option is that your employer can provide you with a loose-fitting Powered Air-Purifying Respirator (PAPR). This a type of respirator that does not depend on a fit between the wearer’s face and the respirator’s facepiece to provide the expected level of protection. Use of this type of respirator would need to be included, and training provided, as part of your employer’s Respiratory Protection Program.

    Another alternative that may be available is for your employer to eliminate the need for you to use a respirator in your work tasks through the assignment/reassignment of work tasks and/or the use of other controls in accordance with a conducted risk assessment to ensure the tasks you perform do not require the use of a respirator.

    They are both flu viruses, and are the same size. The only special thing we have to do is follow the standard precaution rules no matter what the patient may have. We learned this during the SARS episode in Toronto, those people who followed precautions WITHOUT REGARD TO DIAGNOSIS did not contract the dreaded respiratory disease. The more the press concentrates on scaring people, the less our volunteers and employees listen to the basics, and the more illness we will have.

    We are about to complete the first testing cycle and it will take three years to complete the remaining six cycles. While the final report will probably be released in 2014, we may also publish and disseminate progress reports throughout the process.

    So I assume from your post that any time a respirator is required, then fit testing is required also. So I guess we will purchase a respirator fit test kit for our 2 employees who wear a respirator only about once a month. Thanks??

    I agree that fit testing must be mandatory for all those people who need respirators. Their overall health condition is at stake here, so we must do all the things that we can to make sure that their respirators will perfectly fit and work for them.

    Currently, I work for a small hospital and we fit test our staff annually but I was wondering if there is a special course or certificate that the tester must posess to perform the fit testing or is it ok to read the directions and fit test the staff?

    The Occupational Safety and Health Administration’s (OSHA) Respiratory Protection Standard (29 CFR 1910.134) states the respiratory protection program must be administered by a suitably trained program administrator. It further clarifies that the employer shall designate a program administrator who is qualified by appropriate training or experience that is commensurate with the complexity of the program to administer or oversee the respiratory protection program and conduct the required evaluations of program effectiveness, which includes fit testing. There is no special course or certificate the tester needs to obtain to perform fit testing. It’s the respiratory protection administrator’s job to determine if the fit tester is qualified to perform those duties. The American National Standards Institute’s ANSI Z88.10 (2001) has a section on qualifications for persons who conduct respiratory fit testing.

    For more information on FAQs on fit testing and respiratory protection programs, see the NIOSH trusted-source website.

    I am in charge of the RFT program. We have trained additional staff in order that the off shifts may have their test done at a more convenient time. I have one RN trained and feels it is appropriate to perform the Respirator Fit test on herself. Could you provide me with documentation either stating this is inappropiate or to the opposite. Thanks

    While the Occupational Safety and Health Administration’s (OSHA) Respiratory Protection Standard (29 CFR 1910.134) specifically doesn’t say you can’t fit test yourself, it could depend on the OSHA protocol from 1910.134 (A) that is being conducted. Fit test methods are classified as either qualitative or quantitative, and there are multiple protocols of each classification that are OSHA-accepted, ANSI-accepted (Z88.10), or NIOSH-recommended. A qualitative fit test is a pass/fail test to assess the adequacy of respirator fit that relies on the individual’s sensory detection of a test agent. A quantitative fit test numerically measures the effectiveness of the respirator to seal with the wearer’s face, without relying on the wearer’s voluntary or involuntary response to a test agent. A Qualitative Fit Test (QLFT) Protocol maybe more difficult to self administer than a Quantitative Fit Test (QNFT) Protocol. Typically, a respirator fit test protocol requires a facilitator who administers the test and observes the responses of the user being fit tested. Ultimately though, the respiratory protection program administrator at your site should determine if this is appropriate or not for your workplace.

    For more information on FAQs on fit testing and respiratory protection programs, see the NIOSH trusted-source website.

    Hi there. I am trying to find the data on FD line of duty injuries and deaths due to improper facepiece seal, or related cause. Is that information available anywhere?

    Thank you,
    Michael Gallagher, Captain
    Cambria Fire Department, Cambria CA

    Brilliant stuff! Your article is really good, Im glad you took the time to share it.Thanks for sharing your opinion.

    Should each person be fit tested with the respirator issued to them or can one respirator hooked to machhine be used or fit testing. I thought each person had to be tested with their personnel respirator.

    I read through most of the blogs. So- where is NIOSH at with the study? Your response will be much appreciated. Thanks

    What is the weight loss that happens to individuals requiring them to be Re-Fit Tested?

    What would be the correct procedure code in billing for a respirator fit testing done at accrediated facility.

    This is outside of our area of expertise. We recommend contacting your insurance provider. Other blog readers may be able to share information from their experiences.

    I was employed in the oil and gas industry for many years and we were required to work in an environment that had high concentration of H2S (8% H2S). I had trouble passing the fit test because I wear corrective lenses and were not allowed to wear contacts.

    It took 5 fit tests with the proper mask designed especially to fit over prescription glasses. It was a pain but, required never the less. I finally passed but, I am grateful I no longer work in such a dangerous environment.

    An N95 filtering facepiece respirator should be fit tested:
    1) prior to initial use of the respirator;
    2) when a different respirator (size, style, model or make) is used;
    3) when the employee reports a change in physical condition that could affect the respirator fit;
    4) when the employer, supervisor or program administrator observes a physical change in the employee that could affect respirator fit;
    5) and at least annually thereafter.
    Some physical conditions that could affect fit include facial scarring, dental changes, cosmetic surgery, or an obvious change in body weight.

    The Occupational Safety and Health Administration (OSHA) has specific regulations that include fit testing requirements which can be found at:

    I am wondering if NIOSH will be doing any studies pertaining to self contained breathing apparatus (SCBA) in the near future? Individuals working in hydrogen sulfide (h2s) environments must be fit tested and trained yearly and I would like to mention any studies that may be coming up on the following site. I believe this would be very helpful for the people who are potentially exposed to h2s gas in their work environment. []

    Hello Dr. Zhuang,

    I am wondering if there are any preliminary results from the fit testing frequency study.
    I work for Employee Health at Duke in Durham North Carolina. We are wondering if it is possible to decrease the frequency of fit testing.

    I run a drug and alcohol testing center. I would like to offer respiratory fit testing to my site. What do I need to offer this. What are my requirements and equipment needs? Where can I get the training? Thank you.

    There is no special course or certificate the tester needs to obtain to perform fit testing. However, fit testing is one component in a respiratory protection program, and the regulations require you to have a suitably trained program administrator. It’s the respiratory protection administrator’s job to determine if the fit tester is qualified to perform those duties.

    The rules allow you to do either quantitative fit testing (QNFT) or qualitative fit testing (QLFT). Quantitative fit testing requires a device that can measure aerosols inside and outside of a mask and tools needed to “probe” a mask. Qualitative fit testing requires the use of a non-toxic agent that can be sensed (taste or smell) by the person being tested, and often involves use of a personal exposure “tent” in which the non-toxic agent is released.

    An internet search on the two acronyms (QNFT and/or QLFT) will give you many links for sources of equipment or local providers of the service.

    For more information on FAQs on fit testing and respiratory protection programs, see the NIOSH trusted-source website (

    On October 2, 2006, NIOSH issued a letter (Lttr-100206) to all respirator manufacturers regarding the policy for respirator sealing surfaces and facial hair. This particular letter states the following regarding the presence of facial hair and use of a nosecup: “…the nosecup must not come in contact with facial hair, even if there is another seal being used as the primary seal…”

    Is this policy still active? There is a note on the webpage that says the following: “NOTE: This page is archived for historical purposes and is no longer being maintained or updated.” The note is confusing me as to whether or not the policy still stands.

    The NIOSH Policy for Respirator Sealing Surfaces and Facial Hair as described in Letter 100206 is still active. It states “Facial hair that lies along the sealing area of a respirator, such as beards, sideburns, or mustaches will interfere with respirators that rely on a tight facepiece fit to achieve maximum protection. The areas of the skin, which contact the face or neck seal and nosecup seal, must be free of any hair.”

    We apologize for the confusion caused by the note on the web page. The note is required to indicate that the letter, a historical document, is exempt from the internal annual review and update that is required of materials on our website.

    I think Following September 11, 2001 respirator fit testing for workers at the former site of the World Trade Center.I would also like to inquire why the study is using the TSI Portacount as the only analytical tool?

    The ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol using the TSI PortaCount is one of the most common fit test methods. It is not as complicated as other fit test methods and can be used for testing all respirator types including N95 filtering facepiece respirators. The large number of fit tests required by the study makes it an appropriate instrument. In addition, it was found in a NIOSH study to have good correlation with actual exposure (Coffey CC, Campbell DL, Myers WR, Zhuang Z [1998]. Comparison of six respirator fit test methods with an actual measurement of exposure in a simulated health-care environment: part II – method comparison testing. Am Ind Hyg Assoc J 59:862-870).

    I was employed in the oil and gas industry for many years and we were required to work in an environment that had high concentration of H2S (8% H2S). I had trouble passing the fit test because I wear corrective lenses and were not allowed to wear contacts.

    Thank you for your comment. From 1978 to 2005, NIOSH recommended that contact lenses not be worn during work with chemicals that might present risk of eye injury or eye irritation. On review, NIOSH found insufficient data to support that recommendation, and in 2005 NIOSH recommended that workers be permitted to wear contacts, provided that safety guidelines are followed. That is the current guidance. ( Your experience may have been consistent with the recommendations at the time you were working in the oil and gas industry. Respirator manufacturers offer spectacle kits or adapters as accessories for their respirator models. These accessories allow the use of corrective lenses within the respirator’s facepiece without compromising the respirator’s facepiece-to-face seal.

    In your past job, you probably weren’t working in 8% H2S environment; although there may have been contained sources nearby with that concentration of gas. The Immediately Dangerous for Life and Health (IDLH) limit for H2S is 100 ppm, a level at which escape and evacuation is required. The concentration of H2S at 700 to 1,000 ppm results in rapid unconsciousness, cessation of respiration, and death; and 1,000 to 2,000 ppm results in unconsciousness, cessation of respiration, and death in a few minutes. Note that 8% would be 80,000 ppm.

    I have a specific question about homecare visits. Do we need to perform fit testing upon hire and annually thereafter if we do not see patients with undiagnosed TB? Any patient we may receive orders on for home care would have already been diagnosed and ben on medication for at least two weeks, so contagious state is passed. I would like a specific answer to this question regarding home care visits by clinical staff. Our state is low risk and our TB risk analysis is also very low not having seen a TB patient in greater than 5 years. This is extremely timely and we have a large percentage of employees with facial hair that would not meet criteria to even be tested. thanks

    Based on the limited information provided, a fully operational respiratory protection program (RPP) is advised. The fit testing, availability and use of respiratory protection is best employed by the employer through an established RPP as a precaution. If the worker runs into a suspicious case or family member then the fit testing has been completed and respirators are readily available in their home care supplies for use as they deem necessary. While this focuses on TB there is a growing concern about other types of airborne diseases (measles, for example) and an operational RPP mitigates possible exposures for home care workers who are out in the community and may encounter family members or household members who could present an exposure risk. In addition, you may look for interpretive guidance from local public health department and/or local state OSHA representatives.

Post a Comment

Your email address will not be published. Required fields are marked *

All comments posted become a part of the public domain, and users are responsible for their comments. This is a moderated site and your comments will be reviewed before they are posted. Read more about our comment policy »

Page last reviewed: November 1, 2021
Page last updated: November 1, 2021