Wood dust at work poses two main dangers to health in the workplace. The first is that dust getting into the lungs can cause respiratory disease. The second is that wood dust is potentially explosive creating the potential for severe injuries and a fire safety risk in the workplace.
Workplace Hazards of Wood Dust Exposure
Any worker who regularly inhales wood dust may be at risk of Respiratory Disease such as lung cancer and occupational asthma. Wood dust can also be a hazard to eye safety, causing irritation and damage to the eyes.
Employers must therefore limit and control exposure to waste and dust from wood. Exposure to wood dust can be particularly hazardous when it takes place in enclosed spaces.
Wood Dust Explosion Risks
Wood waste and dust is combustible. If wood dust ignites, a flash fire can result. Such a fire can lead to an explosion if the dust is in a contained area where pressure builds up.
Employers should view all wood waste as a source of a potential explosion. If there is any doubt regarding this potential, it’s possible to arrange a dust explosion test.
Should this test show that the mean particle size of the dust is greater than 200 microns, the likelihood is for a weak explosion or none at all. If the mean particle size is less than this, and when 10% or more of the dust has a size less than 80 microns, there is a risk of an explosion.
The results of the test should be passed into a workplace risk assessment, and appropriate measures taken to reduce risks to workplace safety.
Common Wood Dust Waste Hazards
Wood waste is common, but the greatest danger to workers comes when the waste is a fine dust.
Such dust occurs during the cutting of boards. These may be MDF, chipboard or specialist wood sheets.
Machining and sawing hardwoods also creates a fine dust. Working with softwoods generally produces a coarser dust, but there are usually some finer particles present. If these particles separate and gather in a factory or workshop, they may pose the same risk as their hardwood equivalent.
Whatever the type of wood, however, sanding and fine grade cutting creates dust that can be particularly hazardous.
How to Reduce Wood Waste Risks
The most important practical measure to reduce the risks of wood waste is to have an extraction system.
This means that a piece of woodworking machinery should have a ventilation unit. The unit should carry the wood dust to a collection point outside the factory or workshop. There may need to be initial collection points, however, near the machines.
These collection systems must meet design standards. There must be no possible source of ignition, for instance, close to the wood dust at any stage of the collection process.
In brief, the collection system should not have long ducts; should have a pressure gauge to allow workers to check that extraction is working; and should have no signs of damage.
Testing and Maintenance
Safe working practices require a programme of Testing and Maintenance of wood dust extraction systems.
Among other proposals, HSE (Health and Safety Executive) recommends daily checks for signs of wear and tear, and weekly checks for leaks and correct working. HSE also suggests that employers think about installing an air monitoring system.
In addition, employers should arrange daily cleaning of the work areas and machinery.
PPE (Personal Protective Equipment)
Workers should use respiratory PPE when cleaning wood dust from a machine and surrounding areas, and when emptying collection systems. It should not be necessary to wear respiratory PPE at other times if the extraction system does its job properly. They should also wear appropriate eye protection.