Respiratory Protection Fit Testing

Fit Testing

Overview of the Respirator Fit Testing Process

Tight-fitting respirators must seal to the wearer’s face in order to provide expected protection. This includes disposable respirators (also called “filtering facepieces”). Therefore, fit testing is required in Malaysia by the Department of Occupational Safety and Health (DOSH) before a user wears a mandatory respirator on the job, and must be assessed at least annually as highlighted in the Guidelines on The Use of Personal Protective Equipment Against Chemical Hazards, under the Occupational Safety & Health (Use and Standard of Exposure of Chemical Hazardous to Health) Regulations 2000. In addition, fit tests should be performed:

  • Whenever a different size, style, model or make of respirator is used.
  • When any facial changes occur that could affect fit, such as significant weight fluctuation or dental work.

3M Malaysia provides training and certification to our registered fit testers working under our 3M Authorized Distributors (Personal Safety).

  • Qualitative Fit Test (QLFT)

    A qualitative fit test (QLFT) may only be used to fit-test:
     

    • Negative-pressure, air-purifying respirators, as long as they’ll only be used in atmospheres where the hazard is at less than 10 times the permissible exposure limit (PEL).
    • Tight fitting facepieces used with powered and atmosphere-supplying respirators

    3M's QLFT pass/fail relies on the user’s senses using one of four OSHA (US)-accepted test agents:

    • Saccharin (sweet taste); can test respirators with a particulate filter of any class.
    • Bitrex® (bitter taste); can also test respirators with particulate filters of any class.

    Each QLFT method uses seven exercises performed for 1 minute each:

    • Normal breathing.
    • Deep breathing.
    • Moving head side to side.
    • Moving head up and down.
    • Bending over (or jogging in place if fit test unit doesn’t permit bending at the waist).
    • Talking.
    • Normal breathing again.
  • Quantitative Fit Test (QNFT)

    A quantitative fit test (QNFT) can be used to fit-test any tight-fitting respirator. It involves using an instrument to measure leakage around the face seal and produces a numerical result called a “fit factor.” There are three OSHA (US) -accepted QNFT test protocols:

    • Generated aerosol uses a non-hazardous aerosol such as corn oil generated in a test chamber.
    • Condensation nuclei counter (CNC) uses ambient aerosol and doesn’t require a test chamber.
    • Controlled negative pressure (CNP) uses a test that creates a vacuum by temporarily cutting off air. (There is also a fourth method, which is an abbreviated version of this one.)

    QNFTs use the same seven exercises as QLFTs, plus an additional “grimace” test where the subject smiles or frowns for 15 seconds.

    A fit factor of at least 100 is required for half-mask respirators and a minimum fit factor of 500 for a full facepiece negative-pressure respirator. 

    Learn more about Quantitative Fit Testing of Respirators (PDF, 346 KB)


The Importance of Fit

Respirator fit is important because it involves several major issues:
 

  • Seal.
  • Compatibility.
  • Stability.
  • Mask Man

    The Respirator's Seal

    A good fit means the respirator will seal to your skin. A respirator can only work when air passes through the filter. Air will take the path of least resistance, so if the seal isn’t there, the air will go around rather than through the respirator – and therefore lessen the protection.

  • User Seal Check: An Essential Everyday Test

    Employees wearing tight-fitting respiratory protection should perform a seal check each time they put on their respirator, and are required to do so by OSHA regulations unless the use is voluntary. A fit test ensures that the respirator is able to fit and provide a secure seal, but a user seal check ensures that it’s being worn right each time.

    Users can either perform a positive-pressure or negative-pressure seal check:
     

    • A positive-pressure check means blocking the exhalation valve on a half or full facepiece respirator or covering the respirator surface on a filtering facepiece, usually by using your hands, and trying to breathe out. If slight pressure builds up, that means air isn’t leaking around the edges of the respirator.
    • A negative-pressure check involves blocking the intake valves on a half or full facepiece respirator or covering the respirator surface on a filtering facepiece, typically using your hands and trying to breathe in. If no air enters, the seal is tight.

    See the product User Instructions for more details.

  • Compatibility with other PPE

    Safety glasses, hearing protection, face shields, hard hats and coveralls can all vie with a respirator for real estate on a person’s face, head or body. For instance, if a half face respirator doesn’t fit well (especially if it’s too large), it can overlap with glasses. The more that happens, the more fogging can potentially occur on glasses, and the more likely it is that they’ll interfere with the respirator’s seal.

    To catch these problems before they happen on the job, regulations requires any PPE that could interfere with the respirator’s seal to be worn during the fit test.

Fit Hero Video

Fast Facts About Fit Testing

Fit testing is not only required by the regulations; it’s vital to respiratory safety. This list provides some of the whys and hows of fit testing.

  • Fit tests must be performed before employer-mandated use of a tight-fitting respirator, per OSH Regulation.
    In addition, OSH Regulation stipulates that fit testing of employees must occur at least annually; whenever a different size, style, model or make of respirator is used; and when any physical change occurs that could affect fit (such as, for example, significant weight fluctuation, dental work, or other facial changes).
  • Also known as filtering facepieces, these tight-fitting respirators must be fit-tested before mandatory use at a job site.
  • If the employer provides respirators for voluntary use but they aren’t required, they don’t need to be fit-tested – but 3M still recommends it.
  • It is highly recommended that fit testers must be trained and certified by manufacturers to know how to conduct a test, recognize invalid results, and properly clean and maintain equipment. Employers must also have good recordkeeping of all fit testing resuls of every employee.
  • A qualitative fit test (QLFT) may only be used to fit-test certain negative-pressure, air-purifying respirators and positive-pressure, atmosphere-supplying respirators. It relies on the user’s ability to detect a particular taste, smell or irritant. A quantitative fit test (QNFT) can be used to fit-test any tight-fitting respirator. It involves using an instrument to measure leakage around the face seal and produces a numerical result called a “fit factor.”
  • The workplace level of respiratory protection that a respirator or class of respirators is expected to provide to employees when the employer implements a continuing, effective respiratory protection program. Without fit testing, there’s no way of knowing if the respirator is actually able to provide its advertised level of protection for a specific worker.
  • A respirator can only work when air passes through the filter. Air will take the path of least resistance, so if the seal to the face isn’t secure, the air will go around rather than through the respirator. Therefore, it is essential to ensure a proper fit when wearing tight-fitting respirators.
  • Respiratory protection is often worn simultaneously with other personal protective equipment (PPE). Safety glasses, hearing protection, face shields, hard hats and coveralls can all vie with a respirator for real estate on a person’s face, head or body, and could interfere with the respirator’s seal. Fit testing should ensure that equipment is compatible and doesn’t reduce the effectiveness of the respirator due to a compromised face seal.
  • Beards, mustaches, or even stubble interfere with the seal of a tight-fitting respirator. That’s why OSHA requires that employees be clean-shaven the day of the fit test and prohibits any facial hair in areas where the respirator comes into contact with the face.
  • That’s why fit testing involves several exercises, such as head turning and speaking. This determines the respirator’s ability to retain its seal when the worker is in motion.

Fit Test Record

  • Fit Test Record

    The Fit Testing Record is the employer documentation that fit testing has been completed and passed for employees. This record must be kept with the respiratory protection program documentation until the next required fit testing.


Orange background pattern
We're here to help

Got questions? Get in touch with our respiratory protection specialists.

ASK US YOUR QUESTION