Safe Working With Wood Waste

Wood dust poses two main dangers. The first is that it can cause respiratory disease. The second is that it is potentially explosive.

Respiratory Disease

Any worker who regularly inhales wood dust may be at risk of Respiratory Disease. Employers must therefore limit and control exposure to waste and dust from wood.

Explosive

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.

If this test shows 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.

Causes of Wood Waste

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.

Practical Measures

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.