‘Think flash fires’ is the message for some manufacturers from commercial insurance broker, McCarron Coates. Director Luigi Maggio helps highlight the fire risk wood dust can pose within manufacturing.
Flash fires are not as frequently discussed as flash floods but can be equally devastating. They occur when highly combustible wood dust, comprising fine wood particles, are suspended in the air in sufficient concentration and become an easily ignited cloud, potentially set alight by a nearby ignition source. In the worst cases, an explosion can occur.
It is not only wood dust clouds that are latent dangers issue but also stacks of contained wood dust, within which pressure can build. Even a small layer of wood dust left laying on a surface can be a fire hazard. The finer the dust, the higher the explosion risk. Particles under 200 microns are usually explosive, as is a mixture in which as little as 10% of the dust measures under 80 microns. Verifying whether dust is a danger can be achieved through a dust explosion test.
Controlling wood dust is essential, not just because a fire could lead to loss of life but because the law expects employers to be on top of this. The UK legal framework is headed by the Health and Safety at Work Act of 1974, which places a duty of care on the employer. They must take all practicable measures to ensure the health and safety of employees. On top of this there are the Control of Substances Hazardous to Health (COSHH) Regulations of 2002 and Dangerous Substances and Explosive Atmospheres Regulations (DSEAR), 2002. Under this legislation, any manufacturer generating wood dust in their workplace should have procedures in place to assess the risk of explosion and prevent and mitigate it.
McCarron Coates suggests manufacturers refer to the Hierarchy of Controls, of which the very minimum control is protecting workers through use of PPE equipment. “Whilst the use of respiratory protective equipment (RPE) is nowhere near as efficient as eliminating wood dust at source, it will offer some protection,” says Luigi Maggio. “The proviso to this is that protection is dependent on having the right particulate filters within disposable masks, ensuring correct face-fitting of disposable and half masks, and using only special RPE equipment for those with facial hair, for whom certain RPE is not suitable.”
Above this minimum level of protection in the Hierarchy of Controls lies administrative controls, which means changing the way people act around wood dust. For instance, wood dust should not be vacuumed using a standard vacuum, as that could prompt an explosion. Instead, it needs to be picked up by ATEX industrial safety vacuums, with the selection of the right equipment for the individual workplace being a key part of the risk management.
Removing wood dust at source is essential. It is advisable to use LEV systems to capture and extract wood dust-ladened air. Such equipment can operate around processes such as cutting, sanding and shaping wood – all of which generate significant amounts of wood dust.
Catching wood dust before it has a chance to circulate and then taking it away to be treated and filtered in the optimal way is the preferred option. “The LEV equipment again needs to be fit for the facility in which it will operate, with correct product selection being part of the risk management process,” says Luigi Maggio. “Under COSHH regulations, it also needs to be inspected and tested every 14 months. Training staff in all aspects of wood dust control is vital for employee health and for the mitigation of the flash fire risk. Employees need to understand the correct cleaning methods to use, how to wear RPE correctly and the emergency evacuation procedures, should a fire break out. A flash fire can occur out of seemingly nowhere and take hold rapidly.
“Manufacturers must ensure they do all they can to prevent this and abide by the various regulations relevant to wood dust. Over and above that, they should keep a keen eye on their sums insured and work with an expert broker, who understands their sector, to make sure that, should the worst occur and a fire break out, they are not exposed to financial loss by being underinsured.”
