Walk onto almost any construction site and you'll see disposable dust masks pulled down round chins, worn over beards, or so loose you could post a letter through the gap. Respiratory protective equipment (RPE) is one of the most common controls on site — and one of the most consistently misused. The trouble is that a mask only protects the person wearing it if it actually seals to their face. That's where face fit testing comes in, and it's a legal requirement that a surprising number of contractors still skip.
Silica dust, wood dust, asbestos, welding fume, isocyanates in paints — these are not abstract risks. They cause disease that shows up years later, long after the job's finished and invoiced. With the HSE pushing hard on respirable crystalline silica, now is the time to get your RPE and fit testing in order.
What is RPE and where does fit testing come in?
RPE is any device designed to protect the wearer from breathing in harmful substances. It splits broadly into two types:
- Tight-fitting facepieces — disposable masks (FFP2/FFP3), reusable half masks and full-face masks. These rely on a seal against the skin, so they need a face fit test.
- Loose-fitting devices — powered hoods and visors that supply air into a loose headpiece. These don't rely on a skin seal, so they don't need a fit test (though they still need maintenance and training).
Face fit testing matters because faces are all different shapes. A mask that seals perfectly on one worker may leak badly on another. If it leaks, contaminated air is drawn in around the edge and the protection factor on the box means nothing.
RPE is always the last line of defence. Under COSHH you must first try to eliminate or control the hazard at source — water suppression, on-tool extraction (LEV), changing the product, enclosing the task. RPE comes in only when those measures can't reduce exposure to a safe level. If you're reaching for masks first, your COSHH assessment isn't doing its job.
When is a face fit test legally required?
You need a face fit test whenever tight-fitting RPE is used to protect against a substance hazardous to health. In practice that covers a huge amount of site work:
- Cutting, grinding or drilling concrete, stone, brick or tiles (silica)
- Sanding or cutting timber and MDF (wood dust)
- Welding, brazing and hot cutting (metal fume)
- Spray painting and using solvent-based products
- Any work near asbestos (with the right licensing and controls)
- Working with cement, resins and certain adhesives
The requirement sits within the Control of Substances Hazardous to Health Regulations 2002 (COSHH) and, for asbestos, the Control of Asbestos Regulations 2012. Fit testing must be done by a competent tester before the RPE is first used, and repeated if the wearer loses or gains significant weight, has dental work or facial changes, or switches to a different make or model of mask.
The facial hair problem
This is the one that catches people out. Tight-fitting RPE cannot seal through stubble or a beard. Even a day or two of growth breaks the seal. HSE guidance is clear: clean-shaven at the seal area, every shift, for anyone wearing a tight-fitting mask.
If a worker won't or can't shave — on medical or religious grounds — you don't just wave it through. You provide loose-fitting RPE (a powered hood or visor) that doesn't rely on a face seal. Plan this in before the job starts, not when the tester turns up and finds half the gang can't pass.
Common failures HSE sees on site
- No fit testing at all — masks handed out with no record that they seal on the wearer.
- One test, wrong mask — the worker was fit tested on an FFP3 but is actually using a different brand or a half mask on site. The test only covers the specific make and model tested.
- Beards and stubble — defeating the seal entirely.
- No maintenance — reusable masks with perished straps, cracked valves and filters that were never changed.
- RPE as the only control — no LEV, no water suppression, mask doing all the work.
- No training — workers who've never been shown how to fit, check the seal (a quick fit check every time) or store the mask.
Getting it right: a practical checklist
1. Assess the task first. Your COSHH assessment should identify the substance, the exposure and whether RPE is needed after other controls.
2. Select adequate and suitable RPE. Adequate = high enough protection factor for the exposure. Suitable = right for the task, the environment and the wearer.
3. Arrange face fit testing for every wearer of tight-fitting RPE, on the actual make and model they'll use.
4. Record the test — who, what mask, pass or fail, date and tester.
5. Train wearers to fit check every single time before use.
6. Maintain reusable RPE — inspect, clean, replace filters and straps, and keep a record.
7. Brief the gang with a toolbox talk so nobody treats the mask as optional.
A short, documented briefing before dusty work goes a long way. Our toolbox talk templates give you a ready-made format with hazards, controls, a validation Q&A and an attendance record — ideal for a two-minute RPE or dust briefing at the start of a cutting job.
Where RPE fits in your paperwork
RPE and fit testing don't live on their own. They're part of a joined-up set of documents: the COSHH assessment that justifies the control, the task risk assessment, and the method statement that tells people how the work is done safely. If you're unsure how those pieces fit together, the COSHH assessment guide and the difference between a method statement and risk assessment are worth a read.
For dust-heavy trades, a complete COSHH set plus task risk assessments saves you building it all from scratch. The COSHH category and the full Risk Assessment Library Bundle cover the common silica, wood dust and fume tasks in one go.
FAQ
Does a face fit test expire?
There's no fixed legal expiry, but HSE recommends re-testing periodically and whenever the wearer's face changes (weight, dental work, scarring) or the mask make/model changes. Many sites re-test every two years as good practice.
Who can carry out a face fit test?
A competent person — someone suitably trained in the test method. The Fit2Fit accreditation scheme is a recognised way to demonstrate competence, though it isn't legally mandatory.
Can one fit test cover any dust mask?
No. A fit test is specific to the exact make and model tested. Swap to a different mask and the test no longer applies — you'd need to re-test on the new one.
Is an FFP3 disposable mask enough for silica?
Only after other controls (water suppression, on-tool extraction) have reduced exposure as far as reasonably practicable. RPE is the last line, never the first, and it must be fit tested and worn correctly.
Do I need fit testing for powered hoods?
No. Loose-fitting powered RPE doesn't rely on a face seal, so a fit test isn't required — but training, maintenance and flow checks still are.
Get your dust and COSHH paperwork sorted
Face fit testing is only as good as the assessment behind it. Start with the control, document it properly, and keep the records. Grab the COSHH templates and task risk assessments you need, or go unlimited with SafetyPod membership at £69/year and have every template on hand for the next dusty job.