Respiratory Fit Testing: What You Need to Know


What is Fit Testing?

Tight-fitting respirators rely on having a good seal with the wearer’s face, to ensure that the respiratory protective equipment (RPE) will protect the wearer. Fit testing is a method for checking that a facepiece matches the wearer’s facial features and fits well enough to form an adequate seal between the wearer and the RPE.

As people’s faces vary significantly in shape and size, it is unlikely that one type or size of RPE facepiece will fit everyone. Fit testing ensures that the respiratory equipment selected is suitable for the individual wearer. An inadequate fit will significantly reduce the protection provided to the wearer, which may lead to immediate or long-term ill health or even put the wearer’s life in danger.

Who needs a Fit Test?

A fit test should be carried out on any individual who is required to wear tight-fitting RPE the first time they use a particular type of respirator, whether a disposable mask, half mask or full mask.

Respiratory devices that include a loose-fitting hood or constant-flow airline breathing apparatus do not need to be fit tested, but separate appropriate measures should be taken to make sure it is being worn correctly. A fit test should be repeated whenever there is a change to the RPE type, size, model or material or whenever there is a change to the circumstances of the wearer that could alter the fit of the RPE for example: weight loss or gain, substantial dental work, any facial changes (scars, moles, effects of ageing etc) around the face seal area, facial piercings, introduction or change in other head-worn personal protective equipment (PPE).

The Health and Safety Executive (HSE) does not stipulate a frequency of testing, however theFit2Fit RPE Fit Tester Provider Accreditation Scheme recommends that a suitable interval for repeat fit testing is two years. In some situations more frequent repeat fit testing may be appropriate, particularly where RPE is being used as a primary or sole means of control.

Is Fit Testing a legal requirement?

The Health and Safety at Work Act 1974 and the Management of Health and Safety at Work Regulations 1999 require employers to provide and maintain a safe working environment. In addition to the COSHH Regulations 2002, RPE may need to be used to satisfy requirements in the following pieces of legislation:

  • Control of Asbestos Regulations 2012
  • Control of Lead at Work Regulations 2002
  • Ionising Radiations Regulations 1999
  • Confined Spaces Regulations 1997

These Regulations are supported by Approved Codes of Practice (ACOPs), give practical guidance on compliance and have a special status in law. For RPE use that is not covered by any of the above Regulations, employers and employees have duties to follow under the Personal Protective Equipment at Work Regulations 1992.

Who can carry out a Fit Test?

RPE fit testing should be conducted by a competent person who is appropriately trained, qualified and experienced in providing appropriate guidance to respiratory wearers. A list of BSIF-accredited fit testers can be found at the following website:

Following the guidance as specified in INDG 479 is not compulsory and you are free to take other actions. But if you do follow the guidance as specified in INDG 479 you will normally be doing enough to comply with the law. Health and safety inspectors seek to secure compliance with the law and may refer to this guidance as illustration of good practice.

User seal check A pre-use wearer seal check should be carried out each time a fit-tested facepiece is worn and before entering a hazardous environment. This check is to determine whether the wearer has correctly donned a facepiece before entering a contaminated work area.

How do you carry out a Fit Test?

A fit test should always be conducted by a competent individual trained on the fit testing equipment used, and in a suitable environment based on the testing equipment used. The fit tester should always ensure that the testing equipment is in good working order, properly set up and checked or tested before conducting the fit test. It is important to maintain and calibrate the fit testing equipment in accordance with the manufacturer’s instructions.

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

Qualitative Fit Testing (QLFT) The Qualitative method is a pass/fail test based on the wearer’s subjective assessment of any leakage through the face seal region by detecting the introduction of a bitter- or sweet-tasting or fragranced aerosol as a test agent. QLFT methods are suitable for disposable and reusable half masks but are not suitable for full-face masks. This type of test is based on subjective detection and response by the RPE wearer and it is important that it is administered by a fit tester competent in using this method.

Quantitative Fit Testing (QNFT) A Quantitative method provides a numerical measure of how well a facepiece seals against a wearer’s face, which is called a Fit Factor. These tests give an objective measurement of face fit. 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.

Companies who must regularly fit test worker respiratory equipment, such as the fire service, may choose to invest in the ability to carry out tests themselves. A one-off cost for training and purchasing a test instrument enables teams to test their staff on demand.

Fit Testing solutions with Shawcity

Exclusively available from Shawcity in the UK, QuantiFit2 is the industry breakthrough in CNP mask-fit technology.

QuantiFit2 is the first truly portable quantitative fit testing solution. It can now run on battery power for over four hours, allowing use anywhere indoors or even outdoors on site.

Outdoor or undercover testing locations such as marquees offer a healthier environment in terms of COVID contamination and the design and process used by the QuantiFit2 system easily enables relatively contact-free fit testing as well as two metre social distancing while testing several employees simultaneously.

For more information about CNP fit testing or to request a QuantiFit2 demonstration email or call 01367 899553.


Filter Results

News & Events News Events

Register for a Shawcity account

  • Manage your quotations and track order progress
  • Store your contact and delivery information for easy check-out
  • Use the ‘Add to favourites’ feature to make reordering simple.