Managing Dust and Silica on Renovation Sites

Why This Dust Is Worth Taking Seriously

Cutting, grinding, chasing and sanding masonry is part of everyday life on a renovation job. The trouble is that concrete, mortar, brick, stone, tiles and paving all contain crystalline silica, and when you hit them with a disc cutter the fine fraction that floats into the air — respirable crystalline silica, usually shortened to RCS — is small enough to travel deep into your lungs.

Those particles don't come back out. Exposure is linked to silicosis, chronic obstructive pulmonary disease, lung cancer and kidney damage, and the symptoms typically show up years or decades later, long after the job is finished. The HSE workplace exposure limit for RCS is 0.1 mg/m³ averaged over eight hours, which sounds tiny — and it is. A few minutes of dry cutting with a petrol saw can put you well over it. Because it's a long-latency hazard, the sensible tradesperson's approach is simple: assume the dust is harmful, control it at source, and keep it out of your lungs and everyone else's.

Start by Removing the Need to Cut

The cheapest and safest control is not making the dust in the first place. Before you reach for the grinder, ask whether the cut can be avoided or done differently.

• Use a block splitter or bolster chisel rather than cutting blocks and bricks dry.
• Score and snap plasterboard, tiles and cement board by hand where the finish allows.
• Order materials cut to size from the merchant — they carry the risk control, not you.
• Choose a masonry drill bit and a drill with a dust attachment for small holes.
• Keep power tools for cuts that genuinely need them, and cut outside or in a well-ventilated spot if you possibly can.

Planning the sequence of work matters too. Get the dusty tasks done early, before finished surfaces, furniture and carpets are in, and before other trades are working alongside you.

Water Suppression: Cheap and Very Effective

Water knocks dust out of the air and cools the blade, and it works best when it's fed continuously rather than squirted on now and then. Most angle grinders and cut-off saws can be fitted with a water kit, or you can use a constant trickle from a hose or a pressurised bottle feeding directly onto the blade at the point of cut.

Use enough water to make a visible slurry rather than a dry cloud, and remember that slurry is still a hazard once it dries and gets disturbed. Clean it up while it's wet — a squeegee into a bucket, or a wet-rated vacuum — and dispose of it responsibly. Do not wash silica slurry into surface water drains.

Water isn't a complete answer. It reduces dust dramatically but doesn't eliminate it, so it should be paired with extraction or respiratory protection, not used as a substitute for either.

On-Tool Extraction and the Right Class of Vacuum

For grinders, sanders and chase cutters, on-tool extraction connected directly to the machine's shroud is the standard approach. The key point most people get wrong is the class of the vacuum. For silica work in the UK you need at least an M-class unit, and some tasks and larger volumes of hazardous dust will call for H-class. An ordinary workshop or L-class vac will let the finest fraction straight back through the filter and into the room.

• Check the hose and shroud fit — a loose connection leaks dust at the tool head.
• Empty and change filters as the manufacturer specifies, outdoors, wearing RPE, and bag the waste.
• Never shake filters out or blow them with an airline.
• Keep spare filters and bags on the van so a full one doesn't tempt you to run without.

If extraction isn't practical — awkward overhead work, a cut in a tight corner — then the job becomes a short, controlled burst of work with proper RPE, and you should stop and reassess rather than pushing on for an hour.

Masks, Fit Testing and Looking After Your Lungs

Respiratory protective equipment is the last line of defence, not the first. That said, it's essential. For short cutting tasks a disposable FFP3 mask is the minimum; for longer or repeated exposure, a reusable half-mask with P3 filters is more comfortable and seals better.

The mask only works if it fits. That means clean shaven where the seal sits, no beard or stubble breaking the contact, and a proper face fit test — repeated if your face changes shape, if you change mask model, or at least every couple of years. A mask that leaks at the bridge of the nose is giving you a false sense of security.

Think about the rest of the day as well. Wash hands and face before eating, drinking or smoking, and keep food and drinks out of the dusty area. If you're regularly working with silica, ask about health surveillance — lung function checks and a symptoms questionnaire are worth having on record.

Keep Dust Out of the Rest of the House

On domestic renovations the homeowner and other trades are exposed too. Sheet off the work area with polythene, tape doorways, and use a zipped access flap if you're moving in and out. Signage and a quick word with the client go a long way.

Never dry sweep, never use a leaf blower or airline to clear up, and never rely on an open window. Dampen surfaces before sweeping, use an M-class vacuum, and clean up at the end of each shift rather than letting dust build. Small habits, repeated daily, are what keep silica out of your lungs over a career. Do them properly now and you'll still have the breath for the next thirty years of work.