By workplace & process
Wood dust carries hard exposure limits and, for hardwood, a cancer classification. Extraction at the machine is the control - and it only counts if it is tested.
The short answer
Wood dust is not nuisance dust. Hardwood and softwood dust both carry enforced workplace exposure limits, both are respiratory sensitisers that can cause occupational asthma, and hardwood dust is classified as a carcinogen linked to cancer of the nose. Extraction - local exhaust ventilation at the machine - is the control that keeps exposure down, and because the limits are legally enforced, the extraction has to be tested to show it works.
The detail
The workplace exposure limit for hardwood dust is 3 mg per cubic metre as an eight-hour average; for softwood dust it is 5 mg per cubic metre over the same period. Where hardwood and softwood are worked together - which is common - the stricter hardwood limit of 3 mg per cubic metre applies to all the wood dust present. The hardwood limit was tightened to that level in January 2020. Because wood dust is both a sensitiser and, for hardwood, a carcinogen, exposure must also be reduced as low as reasonably practicable, not merely kept under the limit.
Meeting those figures in a real workshop is harder than it looks. HSE research at sites chosen to represent good practice still found a significant share of hardwood and mixed-wood measurements over the limit, with sanding, cleaning and maintenance the worst tasks. Sanders, routers and shapers generate the finest, most respirable dust and are the hardest to capture. Engineered boards add to the arithmetic: MDF is treated as wood dust at the hardwood limit and also carries formaldehyde.
What it means for you
A thorough examination and test of woodworking LEV checks that each machine's extraction is capturing dust at source, that the ducts and dust collector are moving air at the design velocity without leaks or blockages, and that the fan and filters are performing - at least every fourteen months. Duct velocity matters here: wood waste needs enough transport velocity to keep it moving and stop it settling and blocking the run.
The recurring failing is extraction that has lost airflow through a loaded filter or a partially blocked duct, or a hood set too far from the cut, so dust escapes into the breathing zone despite the system running. PPE alone cannot achieve the low exposure a carcinogen demands - the engineering control has to be working, and the test is how that is established.
The service behind the guide
We test dust extraction on woodworking machinery against the exposure limits and capture it must achieve, and report on airflow, ducting and any remedial work.
Questions
Hardwood dust is 3 mg per cubic metre as an eight-hour average and softwood is 5 mg per cubic metre. Where hardwood and softwood are mixed, the stricter 3 mg per cubic metre hardwood limit applies to all the dust.
Hardwood dust is classified as a carcinogen, particularly linked to cancer of the nose. Both hardwood and softwood dust are also respiratory sensitisers that can cause occupational asthma.
Not by itself. Because wood dust is a sensitiser and, for hardwood, a carcinogen, exposure must also be reduced as low as reasonably practicable, not merely held under the workplace exposure limit.
Sanding, routing and shaping generate the finest, most respirable dust and are the hardest to capture. HSE research also found cleaning and maintenance to be high-exposure tasks.
At least every fourteen months under COSHH. The test checks capture at the machine, duct transport velocity, and the condition of the fan, filters and collector.
Phoenix Duct Clean · by the numbers
We examine dust extraction on saws, sanders and routers against the exposure limits it must meet and report clearly. Call or email to book.