FFP3 Dust Masks: Why You Need One for Cutting Brick, Block, and Stone
The UK homeowner's guide to FFP3 masks. When FFP2 isn't enough, what silica dust does to your lungs, disposable vs reusable respirators from ~£9, and how to get a proper seal.
Silica dust is invisible. The particles that do the most damage are too small to see, too small to taste, and too small to make you cough. You breathe them in while cutting a concrete block with an angle grinder, and you feel absolutely fine. Ten years later, you can't walk up a flight of stairs. Silicosis is irreversible, incurable, and kills around 500 UK construction workers every year. An FFP3 mask costs less than two quid. The maths is not complicated.
If your builder is cutting bricks, blocks, roof tiles, or stone on your extension site, and you're anywhere near the dust cloud, you need FFP3 protection. Not FFP2. Not a paper dust mask from the DIY aisle. FFP3.
What it is and when you need one
An FFP3 mask is a respiratory protective device that filters at least 99% of airborne particles. The "FFP" stands for filtering facepiece, and the number (1, 2, or 3) indicates the protection level. FFP1 filters 80%. FFP2 filters 94%. FFP3 filters 99%. The jump from FFP2 to FFP3 sounds small in percentage terms, but the protection factor doubles: an FFP3 mask reduces the dust you breathe by a factor of 20, compared to a factor of 10 for FFP2.
The reason this matters is silica. Respirable crystalline silica (RCS) is a natural component of brick, concrete, stone, mortar, roof tiles, and engineered quartz. When you cut, grind, chase, or drill these materials, the process releases microscopic silica particles into the air. These particles are small enough to reach deep into your lungs, where they cause progressive, irreversible scarring called silicosis. RCS was reclassified as a carcinogen in the UK's 2020 update to EH40 (the workplace exposure limits document). The legal exposure limit is 0.1 mg/m3 over an 8-hour period. Dry-cutting a single concrete block with an angle grinder can exceed that limit in minutes.
EN 149:2001+A1:2009
The European standard (retained in UK law post-Brexit) that certifies FFP masks. FFP3 requires minimum 99% filtration efficiency, maximum 1% filter penetration, and maximum 2% total inward leakage. Look for "EN 149" and "FFP3" printed on the mask itself, not just the box.
The HSE is direct about this: FFP3 is the minimum acceptable grade for any work that generates silica dust. That includes cutting bricks and blocks, cutting or grinding concrete, dry-cutting roof tiles, chasing walls for cables, cutting cement board, and cutting engineered stone worktops. For the highest-risk tasks (cutting blocks or paving with a cut-off saw), the HSE's COSHH Essentials guidance specifies that FFP3 must be combined with water suppression, because the dust levels are too high for respiratory protection alone.
FFP2 is not sufficient for silica dust. This is the single most common mistake homeowners and occasional DIY users make. FFP2 and FFP3 disposable masks look nearly identical. The difference is printed on the mask in small text. Check the rating before you put it on. If you're cutting any masonry material, it must say FFP3.
There are two other situations where FFP3 is specifically required. Stripping pre-1980s paintwork that may contain lead requires FFP3 under the Control of Lead at Work Regulations 2002. And cutting engineered quartz (the material used for high-end kitchen worktops) requires FFP3 at minimum. Engineered stone contains over 90% crystalline silica, compared to roughly 15-30% in standard brick or concrete. In 2024, eight young UK workers (median age 34) were diagnosed with silicosis from cutting engineered stone worktops. Australia banned the material outright. The UK hasn't, but the risk is real.
FFP grades: when you need what
Not every task on an extension needs FFP3. Here's the breakdown.
| Task | Minimum FFP grade | Notes |
|---|---|---|
| Drilling masonry for fixings (rawlplugs, brackets) | FFP2 | Brief exposure, limited dust. FFP3 won't hurt but FFP2 is adequate. |
| Cutting timber with a circular or mitre saw | FFP1 or extraction | Wood dust is hazardous over long exposure but not silica. Extraction at source is better than a mask. |
| Sanding filler or plaster | FFP2 | Fine particles but not silica. Ventilate the room and wear FFP2. |
| Cutting bricks or blocks (angle grinder / cut-off saw) | FFP3 + water suppression | High silica. Wet cutting is the primary control; FFP3 is the backup. |
| Cutting roof tiles (dry) | FFP3 + water suppression | Very high peak exposure. HSE explicitly requires APF 20 (FFP3) for this task. |
| Chasing walls for cables | FFP3 | Grinding mortar and block generates concentrated silica dust in a confined space. |
| Cutting cement board (e.g. Hardie backer) | FFP3 | Contains crystallite silica. Score-and-snap where possible to reduce dust. |
| Stripping pre-1980s paint (heat gun or sanding) | FFP3 | Lead paint risk. CLAW Regulations 2002 specifies APF 20 minimum. |
| Cutting engineered quartz worktops | FFP3 (consider powered RPE) | Over 90% silica content. Professional fabricators use wet cutting and powered air-purifying respirators. |
Types: disposable vs reusable
FFP3 protection comes in two forms, and the choice between them is straightforward.
Disposable FFP3 masks are single-use moulded cups or flat-fold designs with integrated filters. You put one on, do your work, and throw it away. In heavy dust conditions, replace it after 4-5 hours. In lighter, intermittent use, one mask lasts a full day. They come in boxes of 2, 5, or 10.
Reusable half-mask respirators with P3 filter cartridges are rubber or thermoplastic facepieces with replaceable screw-on filter cartridges. The mask itself lasts years. You replace just the filters when they become clogged or after roughly 40 hours of use (follow the manufacturer's guidance). P3 cartridges meet or exceed the 99% filtration threshold of a disposable FFP3.
The decision comes down to how many days you'll be around masonry dust. If you're cutting a handful of blocks for a garden wall, a box of five disposable FFP3 masks is all you need. If your extension involves weeks of blockwork, roof tile cutting, and wall chasing, a reusable half-mask pays for itself within two boxes of disposables and gives you a better, more reliable seal.
Valved vs unvalved. Most FFP3 disposables come with an exhalation valve, a small plastic disc on the front that opens when you breathe out. The valve makes the mask dramatically more comfortable for sustained work because exhaled air escapes directly instead of forcing its way past the filter material. The valve doesn't reduce your inward protection at all. For construction dust work, always buy valved.
The JSP Force 8 half-mask has a feature called PressToCheck: you press the filters inward and if they spring back, the seal is good. It removes the guesswork from seal verification. For a homeowner who won't get a formal face-fit test, this is the most practical way to confirm your mask is actually protecting you.
How to get a proper seal
An FFP3 mask that doesn't seal to your face is just a decoration. The filter material is doing 99% of the work, but only if all the air you breathe passes through it. Any gap at the edges, around the nose, or along the jaw lets unfiltered air straight in.
Fit the nose clip first. On moulded disposable masks, there's a metal strip along the top edge. Pinch it firmly around the bridge of your nose with both hands, moulding it to your face shape. A rounded, gentle pinch works better than a sharp crease. Then pull the lower strap to seat the mask under your chin.
Do a seal check every time. Cover the front of the mask (or the exhalation valve) with both hands. Exhale sharply. The mask should puff outward slightly, with no air leaking at the edges. Then inhale sharply with the mask still covered. It should pull inward and collapse slightly against your face. If you feel air rushing past the nose bridge or along your cheeks, readjust the nose clip and straps.
If you have facial hair, a standard FFP3 won't seal. This isn't a soft guideline. HSE data shows facial hair under the sealing surface causes 20 to 1,000 times more leakage than a clean-shaven face. Even two days of stubble significantly reduces protection. Your options are: shave the area where the mask seals (the jaw line and upper lip for a half-mask), or use a powered air-purifying respirator (PAPR) with a loose-fitting hood that doesn't require a face seal. PAPR hoods are expensive (typically £700 – £1,000+ for a kit) and mainly used by professionals. If you have a beard you won't shave, the realistic answer for occasional DIY use is to stay well upwind of the dust and let someone clean-shaven do the cutting.
A well-fitted FFP2 can outperform a poorly-fitted FFP3 in real-world conditions. The rating on the mask is its maximum theoretical protection. If the seal leaks, you get a fraction of that. Spend thirty seconds on the seal check. It matters more than the number printed on the mask.
What to buy
Disposable FFP3 masks (occasional use)
For a homeowner who needs protection during specific tasks (a day of block cutting, stripping old paint in a room, cutting roof tiles), disposable FFP3 masks are the right choice.
| Product | Quantity | Price | Notes |
|---|---|---|---|
| Screwfix Site FFP3 Valved | 5-pack | ~£9 | Budget pick. Gets the job done. Moulded cup with valve. |
| Delta Plus M1300VC FFP3 Valved | 5-pack | ~£19 | Comfortable contoured shape. Good nose clip. |
| DeWalt FFP3 NR D Valved | 5-pack | ~£20 | Passed dolomite clogging test (D rating) so performs better in very fine dust. |
| DeWalt FFP3 NR D Valved | 10-pack | ~£39 | Better value if you need more than 5. |
| Portwest P301 FFP3 Valved | 10-pack | ~£34 | Good budget option for bulk. |
| Moldex 3200 FFP3 Unvalved | 10-pack | ~£56 | Premium filtration, no valve (hotter to wear). Moldex quality is excellent. |
The "NR" on the packaging means non-reusable (single shift). The "D" means it passed the dolomite clogging test, which indicates the mask maintains airflow longer in very fine dust conditions. For cutting masonry, the D rating is worth having.
Reusable half-mask respirators with P3 filters (regular use)
If your extension involves more than a couple of days of masonry cutting, a reusable half-mask is the better investment. Better seal, more comfortable for hours of wear, and cheaper over time once you factor in filter replacements.
| Product | Price (mask + filters) | Replacement P3 filter pair | Best for |
|---|---|---|---|
| JSP Force 8 Half Mask + P3 PressToCheck filters | ~£24 | ~£8-10 | Best all-rounder. PressToCheck seal verification. Lightweight. Widely available at Toolstation and safety suppliers. |
| Moldex 7000 Series + P3 filters | ~£25 | ~£4.60 | Cheapest replacement filters of any brand. Came first in independent testing (Farmers Weekly). Excellent fit. |
| DeWalt Half Mask Respirator + P3 filters | ~£35 | ~£10 | Available at Toolstation. Pricier and ranked poorly for fit in independent testing. JSP or Moldex are better choices. |
The Moldex 7000 is worth highlighting. In an independent head-to-head test of six reusable half-masks, it came first for weight, fit, and value. Its replacement P3 filters are the cheapest of any major brand, less than half the price of most competitors. If you're doing regular masonry work over a multi-week build, those filter savings add up quickly.
A reusable half-mask costs less than three boxes of five disposable FFP3 masks. If you expect to use more than 15 disposables during your project, the half-mask is cheaper and gives you a better seal. Buy one box of disposables for visitors and the half-mask for yourself.
The FFP2 alternative
If you're only doing tasks that don't generate silica dust (sanding filler, drilling a few holes in masonry for fixings, cutting plasterboard), an FFP2 mask at roughly half the price of FFP3 is adequate. FFP2 filters 94% of particles and provides a protection factor of 10. For short bursts of non-silica dust, that's enough.
But the moment anyone picks up an angle grinder, a masonry saw, or a wall chaser near masonry, FFP2 is not enough. The visual similarity between FFP2 and FFP3 disposables trips people up constantly. Check the printed rating on the mask itself before every use.
Common mistakes
Buying FFP2 by accident. The packaging looks identical. The masks look identical. The only difference is the small print. At Screwfix, the FFP2 and FFP3 boxes sit next to each other on the same shelf. Pick up the wrong one and you've got protection rated for sanding, not for silica. Read the mask, not just the box.
Not replacing disposables often enough. A saturated filter increases breathing resistance, which makes you unconsciously loosen the mask or pull it down below your nose. In heavy dust, replace after 4-5 hours. If the mask feels harder to breathe through than when you first put it on, it's done.
Wearing the mask below your nose. This happens naturally when the mask gets warm and uncomfortable, especially unvalved models. If you catch yourself doing it, stop and take a proper break in clean air. Then put the mask back on properly. This is another reason to buy valved.
Assuming the mask protects against everything. FFP masks filter particles only. They do not protect against solvent fumes, paint vapour, adhesive off-gassing, or any other chemical gas. If you can smell something through the mask, the mask is not designed for that hazard. Organic vapour cartridges (ABEK filters on a reusable half-mask) are a different product entirely.
Working in confined spaces without ventilation. An FFP3 mask filters dust from the air you breathe, but it doesn't add oxygen. In a poorly ventilated room full of dust, the mask buys you time but doesn't solve the problem. Open windows. Run an extraction fan. Use water suppression on the cutting tool. The mask is the last line of defence, not the first.
Where you'll need this
- Walls and blockwork - respiratory protection against silica dust when cutting bricks and blocks
- Roof covering - protection when dry-cutting roof tiles, which produces high silica dust levels
An FFP3 mask belongs in your site bag from the day masonry cutting starts. Keep a box of disposables in the boot of your car so you're never caught without one. If your builder is cutting blocks and you're standing nearby watching, you need a mask too. Silica dust doesn't check whether you're on the payroll.