Sanders make the finest dust in a workshop, and bandsaws throw a steady stream of it below the table. The coarse chips you can sweep up aren’t the problem; the fine dust you can hardly see is, because it hangs in the air and gets breathed in. Good extraction at the machine is the first defence, not a mask.
Why fine dust matters.
The UK’s Health and Safety Executive (HSE) says wood dust can cause asthma, and that hardwood dust can cause cancer, particularly of the nose. Its workplace exposure limits are 3 mg/m³ for hardwood dust and 5 mg/m³ for softwood dust, averaged over an eight-hour day. Those limits are for workplaces, but the dust is the same in a home workshop, and a small closed room fills up quickly.
Extract at the machine.
HSE’s first advice is extraction at the machine, so the dust is captured before it spreads. In practice:
- Use the ports. Most bandsaws have one or two dust ports, usually below the table and at the lower wheel housing; most bench and handheld belt sanders have one too. Connect the extractor to them, using the hose size the manual gives.
- Match the extractor to the machine. A workshop vacuum with a small hose suits handheld sanders, which need high suction through a small port. A larger dust extractor with a wide hose suits a floor-standing bandsaw, which needs a lot of air moving.
- Keep hoses short. Every metre of hose and every bend reduces the airflow. Keep the extractor close and the hose as straight as you can.
- Empty and clean it. A full bag or a clogged filter lets fine dust straight through and cuts the suction. Check the filter rating; a fine filter is what stops the dust you can’t see.
- Clear the machine. Sawdust packed inside a bandsaw’s lower wheel housing affects tracking and can foul the tyre. Vacuum it out when you change the blade.
Cleaning up.
HSE says never to sweep up or use compressed air, because both put the fine dust back into the air. Use a vacuum cleaner that meets at least dust Class M; an ordinary household vacuum lets much of the fine dust through its exhaust.
When to wear a mask as well.
For very dusty jobs such as sanding, HSE says a suitable face mask may be needed in addition to extraction, not instead of it. Choose a mask rated for fine dust, such as FFP3 in the UK and Europe or N95 and better in North America, and make sure it fits tightly; beards stop masks sealing.
Fire.
Fine dust burns. Keep dust off motors and electrical parts, empty extractors before they are full, and never let sparks from a belt grinder near a wood-dust extractor or bag. Use a separate collection for metal grinding.
Organising a small workshop ↗︎Sources
- Health and Safety Executive, “Wood dust: what you need to know”.