Wood dust can cause serious health problems. It can cause asthma, which carpenters and joiners are four times more likely to get compared with other UK workers. The Control of Substances Hazardous to Health (COSHH) Regulations 2002 require that you protect workers from the hazards of wood dust.
Hardwood dust can cause cancer, particularly of the nose.
Settled dust contains the fine particles that are most likely to damage the lungs.
Both hardwood and softwood dusts have a Workplace Exposure Limit (WEL) of 5mg/m3 which must not be exceeded. These are limits placed on the amount of dust in the air, averaged over an eight-hour working day. However, you must reduce exposure to wood dust to as low as ‘reasonably practicable’.
Provide dust extraction (also known as local exhaust ventilation or LEV) at woodworking machines to capture and remove dust before it can spread.
Design the extraction system to take into account:
Educate workers about the risks from wood dust and the control measures required. They should know how to use the extraction properly. Fitting air flow indicators will help, as these will show them if it is working correctly, for example if dampers are open or shut and also if maintenance is required.
Keep the extraction system properly maintained and working correctly (it is a legal requirement to have it examined by a competent person at least every 14 months). Follow the extraction manufacturer’s guidance for maintenance requirements.
Never sweep up or use compressed air lines as this will disturb the dust and allow it to become inhaled. Always clean up using a suitable vacuum cleaner with HEPA filters, or a vacuum attached to the extraction system.
For very dusty jobs such as sanding, additional protection may be needed and a suitable face mask should be worn as well as using the extraction.
Where you need to use RPE you should:
(from BS EN 12779: 2004 Safety of woodworking machines - chip and dust extraction systems with fixed installation - Safety related performances and safety requirements.)
| Machine type | Air flow m3/hr |
|---|---|
| Moulder | 10000 |
| Saw | 2500 |
| saw | 3200 |
| Planer | 6000 |
| Total | 21700 |
Note: Air flow m3/hr = Air velocity (m/s) x Area of duct (m2) x 3600
For a rectangular duct size 10cm by 20cm on a saw the measured air velocity should be 35m/s
2500m3/hr = 0.7m3/s (divide by 3600)
Area of duct is 10cm x 20cm = 0.02m2
Air velocity = 0.7/0.02 = 35m/s
You can find out more about design calculations for combinations of different machines in the Plant design Section of BS EN 12779: 2004 Safety of woodworking machines - Chip and dust extraction systems with fixed installation - Safety related performances and safety requirements.
Because wood dust causes asthma any health effects must be picked up early. This can be done using health surveillance.
For most woods, low level health surveillance will do. When someone first starts in a job where they are exposed to wood dust they should fill in a questionnaire, for example: Sample questionnaire (when worker starts work).
After six weeks they should then complete a follow up questionnaire and this should then be repeated every year, for example: Sample questionnaire (follow-up).
These questionnaires tell you what to do if you think someone has been affected.
A higher level of health surveillance, including lung function testing, is needed for exposures to woods such as western red cedar which are a known asthmagen.
Information sheets & Circular saw poster
Approved Code of Practice and Guidance (ACOP)
DVD: Health and safety in the woodworking industry
BS EN’s for woodworking machines