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Who Needs a Fit Test? Understanding the Importance of Fit Testing

Who Needs a Fit Test?

If you or your employees are required to wear tight-fitting RPE, such as disposable masks, half masks, or full masks, it is essential to undergo a fit test. Fit testing is a crucial process that ensures the proper fit and effectiveness of respiratory protective equipment in preventing the inhalation of harmful airborne particles. In this blog post, we will explore why fit testing is necessary, the legal requirements, types of fit tests, and cost-effective solutions offered by Safety Group for Face Fit Testing.

Legal Requirements for Fit Testing

Under the Health and Safety at Work Act 1974 and the Management of Health and Safety at Work Regulations 1999, employers are obligated to provide and maintain a safe working environment. Fit testing may be required to comply with specific regulations, such as the Control of Asbestos Regulations 2012, Control of Lead at Work Regulations 2002, Control of Substances Hazardous to Health Regulation 2002, or Confined Spaces Regulations 1997.

Who Should Perform Fit Testing?

Fit testing should be conducted by a competent person who is appropriately trained, qualified, and experienced in providing guidance on respiratory wearers. While following the guidance as specified in INDG 479 is not compulsory, it is generally sufficient to comply with the law. Health and safety inspectors may refer to this guidance as an illustration of good practice when assessing compliance.

Types of Fit Tests

There are two basic types of fit tests - qualitative and quantitative methods.

  1. Qualitative Fit Testing (QLFT): This method is a pass/fail test based on the wearer's subjective assessment of any leakage through the face seal region. It involves introducing a bitter- or sweet-tasting or fragranced aerosol as a test agent. QLFT methods are suitable for disposable and reusable half masks but not for full-face masks. It is crucial to administer this test by a fit tester competent in using this method.

  2. Quantitative Fit Testing (QNFT): This method provides a numerical measure of how well a facepiece seals against a wearer's face, known as a Fit Factor. There are two types of QNFT methods: Controlled Negative Pressure (CNP) and Ambient Particle Counting (APC).

  • CNP fit testing can be carried out in any test conditions, clean or dirty air, indoors or outdoors, as it measures the amount of air leaking out of the mask when controlled negative pressure is applied to create a vacuum. CNP tests full- and half-face masks but not disposables. It has no contamination issues so therefore low maintenance and cost of ownership. The CNP method offers reduced contact, is the easiest to sanitise between tests and has seen a recent surge in popularity, especially during the COVID pandemic.

  • APC requires specific indoor test conditions as the instrument counts the number of particles inside the mask, compared to the number of particles external to the mask. If there is not enough particulate in the air, the tester will introduce artificial particulate through the use of salt fog or lit candles or wicks. APC is suitable for testing full- and half-face masks as well as disposables. It incurs a certain level of maintenance due to contamination and also cost of ownership due to consumables.

How much does a Fit Test cost?

The cost of a fit test will depend on the type of fit testing method used and whether a trained fit testing professional is hired to provide fit tests on behalf of the employer. It is more cost-effective to engage the services of a fit tester to test employees in bulk where possible. Safety Group offer a number of solutions to Face Fit Testing. Get in touch for further information.

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