Back to Knowledge Hub PPE Guide · 7 min read

Face Masks — the full guide

FFP1, FFP2, FFP3, half-mask, full-face. Here’s when to use each, what the HSE actually requires, and the fit-test rule everyone on site gets wrong.

By Watkins Academy Updated April 2026 7 min read

99% Particulate filtered by an FFP3 respirator (to EN149)

500+/yr UK silicosis deaths linked to respirable crystalline silica in construction

50% RPE fit-test failure rate on first attempt (HSE research)

Reg 7COSHH The regulation that makes fit-testing a legal requirement, not a nice-to-have

Sources: HSE, EN149:2001, IOSH. Figures are indicative UK values based on the most recent published reporting.

The three FFP ratings

Filtering Face-Piece (FFP) disposable masks are rated under EN 149:2001+A1:2009 by how much airborne particulate they filter and how much total inward leakage is permitted. The higher the number, the greater the protection — and, usually, the greater the breathing resistance.

FFP1 78% filtered

Good for Nuisance dust, DIY sanding, low-level pollen or mould in well-ventilated spaces.

Not for Silica, asbestos, lead, biological hazards, any health-critical exposure.

Max leakage 22% total inward leakage allowed under EN 149

FFP2 94% filtered

Good for General construction dust, wood dust, MDF, insulation, mould, low-level welding fume.

Not for Silica (RCS), asbestos, lead, isocyanates — FFP3 minimum for those.

Max leakage 8% total inward leakage allowed under EN 149

FFP3 99% filtered

Good for Respirable crystalline silica, asbestos (bonded + limited), lead, biologicals, spray-paint overspray.

Not for Vapours, solvents, gases — those need a cartridge respirator, not a particulate filter.

Max leakage 2% total inward leakage allowed under EN 149

Rule of thumb: if you’re not sure, go one rating up. A short-term over-specification costs pennies. An under-specification on silica or asbestos costs lungs.

Beyond FFP: half-mask, full-face, PAPR

Disposables are the right answer for low-to-moderate dust exposure over short durations. For longer exposures, higher hazard, or workers who can’t clean-shave (more on that below), you step up to reusable RPE.

Reusable half-mask

P3 filter — filters 99.95%. Fits over nose and mouth. Twin-cartridge filters can be swapped for particulate (P3), organic vapour (A2) or combined. Cleans with wipes, stores in a sealed box, lasts years. Needs fit-testing.

Full-face respirator

Combined A2/P3. Protects eyes as well as airways — essential for isocyanates, spray paints, solvents, sewer work. Better seal than half-mask and mandatory for certain licensed-asbestos work. Still needs fit-testing.

PAPR (powered air)

Loose-fitting hood or helmet. Battery-powered fan draws air through a filter and delivers it under positive pressure — no face seal required, so it works for bearded operatives. High protection, low breathing effort, but costs more and needs battery/filter management.

Fit-testing — the bit everyone gets wrong

Any tight-fitting RPE — disposable FFP, half-mask, full-face — must be fit-tested on the individual who will wear it. Not on “a colleague the same size.” Not on “the last site.” On the person, on the specific make and model, before they wear it for work. That is the COSHH Regulation 7 requirement, and it applies on every UK site.

Qualitative (QLFT)

A bitter or sweet test solution is sprayed under a hood while the wearer performs a series of movements. If they can taste it, the mask has failed.

Used for disposables and half-masks (not FFP3 in high-hazard work)
Cheaper, portable, no equipment beyond a hood and test kit
Pass/fail is subjective — depends on the wearer’s taste sensitivity

Quantitative (QNFT)

A particle counter (Portacount or similar) measures particle concentration inside and outside the mask, calculating a numerical fit-factor.

Required for full-face respirators and all high-hazard work
Objective, measured, documented — no ambiguity on pass/fail
Preferred for silica, asbestos, lead and licensed work

The clean-shaven rule: any tight-fitting RPE must be worn on a clean-shaven face at the seal line. Stubble, a goatee, a beard, even heavy sideburns — any of them break the seal and the rated protection drops to zero. For bearded workers, switch to a PAPR or loose-fitting hood. Full stop.

Matching the mask to the hazard

The right RPE depends on the substance, its form (dust, fume, mist, vapour) and the duration of exposure. Use this as a starting point — always cross-reference with the COSHH assessment for the specific task.

Hazard	Minimum RPE	Fit test
General site dust, sweeping, light sanding	FFP2 disposable	Qualitative fit test annually
Wood dust (hard & soft), MDF, cutting timber	FFP2 or FFP3 (MDF)	Qualitative fit test annually
Respirable Crystalline Silica — concrete, brick, stone cutting	FFP3 disposable or half-mask + P3 filter	Quantitative preferred
Asbestos (non-licensed / NNLW)	FFP3 disposable or half-mask + P3 filter	Quantitative, documented
Asbestos (licensed work)	Full-face respirator, P3 or PAPR	Quantitative, documented
Lead (soldering, demolition, stripping)	Half-mask + P3 or full-face	Quantitative
Welding fume (mild steel)	PAPR welding helmet (HSE guidance)	Manufacturer fit-test
Spray paint, solvents, isocyanates	Full-face respirator, combined A2/P3 cartridge	Quantitative
Biological (mould, sewage, bird droppings)	FFP3 disposable minimum	Quantitative preferred

The seal check — do this every single time

Even after a formal fit test, a wearer needs to check the seal on every occasion the mask goes on. It takes ten seconds and catches the damage, the twisted strap, the dislodged nose-clip that a fit-test last year can’t.

1
Position and tighten
Mask centred on nose and chin, nose-clip pinched to the shape of your nose, both straps behind the head at the correct heights (never crossed, never on top of each other).
2
Positive-pressure check
Cup both hands over the mask without pressing down. Exhale sharply. You should feel the mask balloon outward very slightly — no air should escape around the edges. If it does, reseat and try again.
3
Negative-pressure check
Inhale sharply. The mask should pull in slightly towards your face and hold. If it collapses in easily or air leaks in around the edges, the fit has failed. Don’t work in it — reseat, swap it, or escalate.

Care, storage & replacement

Disposables: single-use, single-shift. Bin it at the end of the task — do not hang on a hook or in a cab for tomorrow.
Half- and full-face: wipe down the facepiece after each shift with a manufacturer-approved wipe. Store in a sealed box, out of direct sunlight, away from solvents.
Filter replacement: follow the manufacturer’s change-out schedule. Particulate filters get changed when breathing resistance rises; gas/vapour cartridges on a time basis, whether or not they “smell used.”
Records: maintain a written inspection log for reusable RPE. Fit-test certificates renewed annually and whenever a wearer’s face changes (significant weight change, dentures, surgery, scars).

Common mistakes — and why they keep happening

Wearing over stubble

A single day’s growth breaks the seal. Any tight-fitting RPE must be worn on a clean-shaven face at the seal line — even a goatee or sideburns will fail. PAPR or loose-fitting hoods are the answer for beards.

Reusing a disposable

Disposables are single-use, single-shift. Hanging one on a hook for tomorrow collapses the fibre-charge and loses the fit. If it’s been taken off, it’s done.

Relying on “it feels tight”

Subjective comfort is not a fit test. Every tight-fitting RPE must be fit-tested on the individual wearer (COSHH Reg. 7). No certificate, no wear.

What site leaders should lock in

Face-fit testing on every tight-fitting RPE before issue. No certificate, no mask, no task. Record it centrally and set a 12-month diary reminder for renewal.
Clean-shave standard in the site induction pack. Make it clear in advance — so a bearded operative turning up on day one is met with a PAPR, not a problem.
Stock the right spec per hazard on site. A box of FFP2s doesn’t cover a silica task. Match your RPE stock to the COSHH register.
Monthly RPE inspection for reusable half- and full-face masks. Valve integrity, head-harness elasticity, cartridge date.
Retest when faces change. Significant weight change, dental work, facial injury — triggers an immediate re-test, not a wait for the annual.