Phoenix Journal · LEV & Air Quality
A joinery workshop generates dust with every cut, and some of that dust causes cancer. Hardwood dust is a recognised carcinogen, yet it is still often treated as a housekeeping nuisance. Controlling it well is a design job, not a sweeping-up job.
Every cut, rip and sanding pass in a joinery workshop throws wood dust into the air, and the temptation is to treat the result as mess to be swept up at the end of the day. That framing is the root of most of what goes wrong. Wood dust is not a tidiness issue, it is a substance controlled under COSHH, and hardwood dust in particular is a recognised carcinogen linked to cancer of the nose. The finest dust, the part you can barely see settling on a bench, is the part most likely to reach the lung.
The distinction between species matters for the paperwork and the controls. Hardwood dust is classed as carcinogenic, and both hardwood and softwood dusts can cause asthma and dermatitis through respiratory and skin sensitisation. Engineered boards do not escape this: for exposure limit purposes the HSE treats MDF as wood dust, and MDF also carries formaldehyde from its resin, so a board that machines cleanly can still be one of the more hazardous materials on the bench.
Time is the other trap. Carcinogens rarely announce themselves, and there is usually more than a decade between exposure and any sign of ill health, so a workshop can run for years feeling entirely fine while the risk quietly accrues. That gap is exactly why control has to be judged on the dust in the air today, not on whether anyone has fallen ill yet.
Limits that were tightened
Both hardwood and softwood dusts carry a workplace exposure limit that must not be exceeded. The hardwood limit is 3 mg/m3 as an eight-hour average, reduced from 5 back in January 2020, and the softwood limit is 5 mg/m3. Where a workshop machines a mixture of the two, which most do, the lower hardwood figure of 3 mg/m3 applies to all the wood dust present, so mixed working effectively pulls everyone down to the stricter number. Species matters too: western red cedar, though a softwood, contains plicatic acid and can cause asthma well below the hardwood limit, a reminder that the figures are a floor rather than a full picture.
Meeting the limit is the floor, not the goal. Because hardwood dust is a carcinogen and both types are sensitisers, COSHH requires exposure to be reduced as low as is reasonably practicable, not merely held under the figure. HSE research drives the point home: across a set of sites chosen as representative of good practice, a meaningful share of hardwood and mixed-wood measurements still came out above 3 mg/m3, which tells you how easily a workshop that feels clean can breach the limit without proper engineering.
The reason engineering matters more than good intentions is simple: if the extraction is not designed, installed and verified to hold the dust below the limit, no amount of care with a brush or a mask will close the gap. Protective masks help the individual wearing one correctly, but they cannot substitute for capturing the dust before it fills the room.
Capture at the machine
The primary control in joinery is local exhaust ventilation at each machine, sized to capture the dust the tool actually produces before it spreads. Saws, planers, sanders and routers each throw dust differently, and a receiving hood that is too small or set too far from the cut will miss the fastest-moving particles, which are the ones that travel. Just as important is what you never do: dry sweeping and compressed air lines simply relaunch the finest, most harmful dust back into the breathing zone, so cleaning is done with an industrial vacuum fitted with the right high-efficiency filter. Portable tools deserve the same discipline, with on-tool extraction fitted to hand-held sanders and routers rather than left to a nearby duct to catch what it can. The health case behind all of this is set out in wood dust, the workshop hazard that is easy to underestimate, which explains why such a familiar material earns some of the tightest limits in the shop.
Backing up the extraction
Even good extraction leaves residual dust during some tasks, so respiratory protection has a role as the last line, not the first. The catch is that a mask only protects the person wearing it if it seals to their face, which is why the fit has to be proven for the individual rather than assumed from the box. That is the whole argument of face fit testing, why it is not optional: a tight-fitting mask that leaks gives false confidence, which is worse than knowing you are exposed. Alongside the hardware, the LEV itself is subject to thorough examination and testing under COSHH, and health surveillance should pick up early respiratory or skin changes while they can still be acted on.
Questions
Hardwood dust is classified as a carcinogen and is linked to cancer of the nose. Softwood dust and MDF are respiratory sensitisers that can cause asthma and dermatitis. Because a carcinogen is involved, exposure must be reduced as low as reasonably practicable.
The hardwood limit is 3 mg/m3 over an eight-hour day and the softwood limit is 5 mg/m3. For a mix of hardwood and softwood, the lower 3 mg/m3 figure applies to all the wood dust present.
No. Dry sweeping and compressed air throw the finest, most harmful dust back into the air. Clean with an industrial vacuum fitted with the right high-efficiency filter, and rely on extraction at each machine rather than tidying up afterwards.
Phoenix Duct Clean · by the numbers
Wood dust LEV has to be designed, installed and tested to hold a carcinogen below its limit. Phoenix examines and tests LEV to COSHH Regulation 9 and reports on real capture, not just airflow. UK-wide.