What Is Face Fit Testing?

“When your team relies on respirators to stay safe, the seal either works, or it doesn’t.”

When your team relies on respirators to stay safe, the seal either works, or it doesn’t. Face fit testing is how you prove it.

This guide explains what face fit testing is, when it’s required, how it’s carried out, and what UK employers need to have in place.

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What is face fit testing?

Face fit testing is a practical examination of how well a tight-fitting respirator seals to an individual wearer’s face. The performance of tight-fitting RPE depends on continuous contact between the face seal and the wearer’s skin. If the seal leaks, contaminated air can bypass the filter and be inhaled.

Because faces and masks come in different shapes and sizes, it is unlikely that one make or size will suit everyone. The role of the fit test is to confirm that a particular make, model, type and size of mask is suitable for a specific worker – and to pick up when it is not.

Face fit testing:

Applies to tight-fitting facepieces such as:

• Disposable FFP1, FFP2 and FFP3 filtering facepieces
• Reusable half-mask respirators
• Full-face respirators, including those used with powered or supplied-air systems under positive pressure

Does not apply to loose-fitting hoods, helmets, visors or suits, where protection is provided by a flow of clean air rather than a tight face seal. Those devices still have to be correctly selected, used and maintained under your RPE programme.

A formal face fit test sits alongside (not instead of) the simple fit checks workers should perform every time they put their mask on. Fit testing is periodic and documented; fit checks are routine, user-led checks before each use. Both are required for reliable protection.

If your staff use tight-fitting RPE, a formal test with a competent provider is required. Velocity Safety offers on-site qualitative and quantitative face fit testing for all mask types.

Fit checks vs fit tests – what’s the difference?

A fit test is a formal, periodic assessment carried out by a competent person to prove a specific mask seals to a specific wearer. It must follow HSE INDG 479 and be documented.

A fit check (or user seal check) is a quick self-check the wearer performs every time they put the mask on. It is not a substitute for a formal test.

Both are required for tight-fitting RPE to protect properly.

Is face fit testing a legal requirement in the UK?

The law requires employers to prevent or adequately control exposure to hazardous substances at work. Where RPE is relied on as part of that control, it must be adequate and suitable for each wearer.

The HSE and supporting Approved Codes of Practice make it clear that for tight-fitting RPE, this includes fit testing:

• HSE’s RPE FAQ states that fit testing is required to ensure the selected RPE is suitable for the wearer and that tight-fitting facepieces must fit the wearer’s face to be effective.
• The Fit2Fit / BSIF scheme explicitly notes that it is a legal requirement for workers using tight-fitting RPE under COSHH to be fit tested by a competent person.
• HSE’s HSG53 and INDG479 (rev2, October 2025) provide detailed guidance on RPE selection and fit testing methods.

In practice, if you issue tight-fitting RPE as a control measure under COSHH, the Control of Asbestos Regulations or the Control of Lead at Work, you should treat face fit testing by a competent person as part of your legal duty to ensure the RPE is adequate and suitable.

Which masks actually need a face fit test?

Not all masks are treated the same way under UK guidance. The key question is whether the respirator relies on a tight seal to the face or a flow of clean air around the head and shoulders. If protection depends on a seal with the skin, HSE and the supporting ACOPs expect it to be fit tested by a competent person.

Tight-fitting RPE – fit test required

Fit testing is required for any tight-fitting respirator where protection depends on a seal to the face, for example:

• Disposable filtering facepieces (FFP1, FFP2, FFP3)
• Reusable half-mask respirators
• Full-face respirators
• Tight-fitting powered respirators and airline systems that use a mask or full-face piece with a seal

Each different type of tight-fitting facepiece that a worker uses should be fit tested – different models, and often different sizes within the same range, need their own test. HSE+1

Loose-fitting RPE – fit test not required

Loose-fitting devices do not require face fit testing, including:

• Loose-fitting powered hoods and helmets
• Loose-fitting visors and suits supplied with clean air

These rely on a flow of clean air rather than a face seal. They are often used where clean-shaven policies cannot be followed – for example, because of religious reasons or certain medical conditions. They still need to be correctly selected, maintained and used as part of a wider RPE programme.

How is face fit testing carried out?

HSE recognises two basic types of RPE fit testing: qualitative and quantitative. Both are set out in INDG479 and supported by Fit2Fit companion documents.

Qualitative fit testing (QLFT)

Qualitative testing is often called the “taste test”. It is a pass/fail method based on whether the wearer can detect a bitter or sweet aerosol while performing a set of test exercises under a hood.

Key points:

• Suitable for disposable FFP masks and reusable half masks
• Not suitable for full-face masks
• Involves a sensitivity test (no mask) followed by the fit test itself
• Relies on the wearer’s taste response, so the procedure and communication need to be clear

Quantitative fit testing (QNFT)

Quantitative methods use an instrument to measure how much leakage occurs into the mask and provide a numerical fit factor. Common methods include ambient particle counting and controlled negative pressure.

Key points:

• Suitable for disposable and reusable half masks and full-face masks
• Gives an objective fit factor rather than a simple pass/fail based only on taste
• Particularly useful where higher protection factors are required or where qualitative testing is not appropriate

INDG479 test exercises

Whatever method is used, INDG479 specifies a series of fit test exercises – for example normal breathing, deep breathing, turning the head, moving the head up and down, talking and bending. The wearer needs to maintain an adequate fit throughout all exercises in one continuous test.

When should face fit testing be done – and how often?

Fit testing isn’t something you do once and forget about. It has to run alongside your wider RPE and COSHH programme. HSE expects it to be part of the whole lifecycle of RPE – from initial selection through to periodic review. You’re checking that the mask you’ve chosen is still suitable for the face it sits on, and that nothing has changed that would undermine the seal.

Initial testing

The best time to do a fit test is at the initial RPE selection stage, before the respirator is used in the workplace. HSE states that individual users should be given a choice of adequate models, and that the specific make, model, type and size worn during a successful test must then be made available for normal use.

A fit test should also be carried out whenever a worker starts using a new type, model or size of tight-fitting respirator.

Repeat testing

INDG479 (rev2) and HSE guidance require employers to have a system for reviewing when repeat fit testing is needed. They do not set a fixed legal retest period.

Fit2Fit and related BSIF guidance recommend:

• A repeat fit test at least every 2 years as a sensible interval for most workplaces
• More frequent testing (often annually) where RPE is a primary or sole means of control, or where risks are particularly high

A new fit test is also required if:

• The make, model, size or material of the respirator changes
• The wearer experiences significant weight loss or gain
• There are facial changes around the seal area (scars, moles, surgery, piercings, ageing)
• The wearer has major dental work
• Other head-worn PPE (e.g. spectacles, goggles, helmets, visors) changes in a way that could interfere with the seal

As part of your RPE programme, it’s good practice to record an agreed repeat test date or interval in the fit test report and keep those records for several years (many organisations aim for at least five).

What happens during a face fit test?

From a worker’s point of view, a typical face fit test looks like this (exact details vary depending on method):

Pre-test checks and questionnaire

• Basic health and suitability questions
• Confirmation of mask make, model, size and filters
• Check that the RPE is in good condition

Clean-shaven and PPE check

• For tight-fitting masks, the wearer should be clean-shaven in the seal area; stubble and beards prevent a proper seal.
• Any items that could interfere with the seal (jewellery, certain piercings, hair, some spectacles) may need to be removed or adjusted.

Donning and user training

• Instruction and coaching on how to put the mask on, adjust straps, and perform a user seal check.

Sensitivity test (qualitative methods)

• For taste-based tests, the wearer first sits under the hood without a mask while the bitter or sweet solution is sprayed in.
• The tester records how many sprays it takes for the wearer to taste the solution.

Fit test exercises

• With the mask on (and hood if qualitative), the wearer performs a sequence of exercises: normal breathing, deep breathing, moving the head side-to-side and up-and-down, speaking, and bending.
• For qualitative tests, any taste means the test has failed.
• For quantitative tests, the instrument calculates a fit factor and confirms whether it meets the required level.

Result and report

• The tester explains whether the mask passed or failed.
• A fit test report is produced, typically including the wearer’s details, RPE details, method used, result, date and recommended retest interval. H
• If the wearer fails, the tester will usually help them identify an alternative mask (different model or size) to try, and repeat the process.

Who can carry out face fit testing?

HSE is clear that RPE fit testing should be conducted by a competent person.

Competence in this context means someone who:

• Is appropriately trained, qualified and experienced
• Understands the relevant HSE guidance (INDG479, HSG53) and test protocols
• Uses suitable, calibrated equipment and follows the correct method
• Can recognise when test conditions, mask selection or user behaviour are undermining the result

The Fit2Fit RPE Fit Test Providers Accreditation Scheme, operated by BSIF, is widely used to demonstrate competence. HSE explicitly points employers to the scheme as a way to help decide if a fit tester is competent.

Accreditation is not a legal requirement in itself, but using a Fit2Fit-accredited provider provides strong evidence that you have taken reasonable steps to ensure competence.

If you need testing carried out by a competent, Fit2Fit-accredited provider, Velocity Safety delivers both qualitative and quantitative face fit testing on-site across the UK.

Common myths and mistakes about face fit testing

A few patterns crop up again and again:

“They’ve worn masks for years; they don’t need a test.”

Experience does not guarantee fit. HSE data and Fit2Fit research suggest a significant proportion of RPE in use does not offer the level of protection assumed, often due to poor fit.

“One fit test covers any mask we buy.”

Fit testing is mask-specific. A pass only covers the particular make, model, type and size worn during the test. Change the mask and you need a new test.

“We did Covid FFP3 testing – that’s us sorted forever.”

Face shape changes with time, weight, dental work and ageing. Fit2Fit guidance recommends retesting at regular intervals (typically every 2 years or more often) and whenever relevant changes occur.

“Beards are fine if the mask looks snug.”

HSE emphasises that stubble and beards make it impossible to get a good seal with tight-fitting masks. Those wearers either need to be clean-shaven in the seal area or use loose-fitting RPE.

“Any training provider can do fit testing.”

HSE expects a competent person using recognised protocols. If something goes wrong, you’ll want to show that your tester had appropriate training, followed INDG479 and, ideally, held Fit2Fit accreditation or equivalent evidence of competence.

What employers should have in place

In practice, a compliant RPE and face fit programme usually includes:

Risk assessment and RPE selection

• COSHH (and other relevant) assessments that justify using RPE
• RPE selected for the specific hazard, environment, task and wearer, following HSG53

Face fit testing programme

• Initial fit testing at selection stage for all tight-fitting RPE users
• Clear criteria for repeat testing (mask changes, facial changes, time-based interval)
• Use of competent testers, ideally Fit2Fit-accredited

Policies on facial hair and compatibility with other PPE

• Written rules on clean-shaven requirements for tight-fitting masks
• Procedures for staff who cannot shave (e.g. allocation of suitable loose-fitting RPE)

Training and supervision

• Workers trained to don and doff masks, carry out daily fit checks and look after their RPE
• Supervisors who know when to challenge poor use or non-compliance

Maintenance, storage and record-keeping

• Maintenance and inspection regime for reusable RPE
• Suitable storage to prevent damage and contamination
• Fit test records retained for an appropriate period (commonly at least 5 years)

How much does face fit testing cost?

Face fit testing in the UK is typically priced per session or per engineer day, depending on the number of staff being tested and whether qualitative or quantitative methods are required.

Velocity Safety’s standard pricing is:

• Half day (8–10 tests): £450 + VAT
• Full day (10–18 tests): £595 + VAT

Factors that affect cost include:

• Whether testing is qualitative (Bitrex/Saccharin) or quantitative (Portacount)
• Travel requirements
• How many different mask models staff need to be tested on
• Whether refresher training or operator training is included
• Multi-site or multi-day scheduling

For larger teams, contractors or NHS Trusts, day-rate or multi-day pricing is normally the most efficient option.

👉 See full pricing and availability on our Face Fit Testing service page

How Velocity Safety Can Help

FAQs

Face fit testing always throws up the same practical questions. Here are the ones we get asked most – with clear, HSE-aligned answers.

Is face fit testing a legal requirement?

Where tight-fitting RPE is used as a control measure under COSHH and related regulations, HSE expects it to be fit tested by a competent person. BSIF/ Fit2Fit guidance describes this as a legal requirement under COSHH for tight-fitting RPE.

How long does a face fit test last?

A typical test for one mask usually takes around 20–45 minutes per person, depending on the method and how much training is needed. Qualitative tests tend to be shorter; quantitative tests can take longer.

How long is a face fit test valid for?

There is no fixed legal expiry date. Current HSE/INDG479 guidance requires you to have a system to review when repeat testing is required. Fit2Fit/BSIF guidance and many professional bodies recommend retesting at least every 2 years, or more often in high-risk environments.

Do workers with beards automatically fail?

For tight-fitting masks, facial hair in the seal area prevents a reliable fit, so those workers should normally use loose-fitting RPE instead. HSE guidance is very clear that stubble and beards make a good seal impossible on tight-fitting facepieces.

Do we have to test agency staff and contractors?

Yes – if they use tight-fitting RPE under your control measures, they still require suitable fit testing and training. How you arrange that (in-house, via their employer, or via a third-party provider) is a contractual and practical question, but the duty to ensure adequate protection remains.

If you need accredited fit testing for your workplace or healthcare setting, Velocity Safety delivers Bitrex/Saccharin and Portacount testing UK-wide.

Resources

If you want to dive into the source guidance behind this article, these are the key documents and pages to refer to:

• • INDG479 (rev2, October 2025) – Guidance on RPE fit testing
  • HSE: Fit testing basics
  • HSG53 – Respiratory protective equipment at work: A practical guide
  • HSE: Respiratory protective equipment (RPE) basics
  • HSE: Advice for employers on RPE
  • Fit2Fit RPE Fit Test Providers Accreditation Scheme (BSIF)
  • Repeat fit testing guidance (Fit2Fit-aligned providers)

Next steps for UK employers

If you need help delivering compliant face fit testing, maintaining RPE records or supporting upcoming audits, Velocity Safety can support across your entire respiratory protection programme:

• Face Fit Testing & Certification
• NHS & Healthcare Face Fit Testing & Training
• RPE Examination & Servicing
• Respiratory Protective Equipment Inspections
• Breathing Air Testing
• Local Exhaust Ventilation (LEV) Thorough Examination & Testing
• Pressure Systems Safety Regulations (PSSR 2000) Examinations
• Filter Integrity (DOP) Testing

Used together, these services give you an end-to-end approach – from the quality of the air being supplied, through to mask fit, RPE condition and the records auditors expect to see.