How dust can be a hazard in your workplace

It is important that your team understands the dangers of dust in a manufacturing workplace to be able to help eliminate risks.

There are certain conditions that will make dust a highly dangerous substance

• Dust from materials such as wood, sugar, coal, grain or plastic are highly flammable
• Dust particles that might be in the air can be more oxygenated, also making them highly flammable
• Build ups of dust concentrated in a confined area
• A confined space inside a building
• Concentrated piles of dust
• An ignition source, such as open flames, hot surfaces, warm machinery or electrical discharges

An explosion caused by combustible materials in dust form is likely to be severe  as a result of high amount of dispersed materials with a large surface area being exposed to  air. In contrast, the same mass of a solid combustible material as a heap or pile will burn relatively slowly owing to the limited surface area exposed to the oxygen of the air. If there is an explosion, remove yourself from the area as soon as possible.

In 1981 an explosion at a plant in Banbury which manufactured custard powder injured nine men and caused substantial damage to an external wall of the building. A fault in a pneumatic conveying system caused a holding bin to overfill and the air pressure caused the bin to fail. The released custard powder ignited as a dust cloud within the building.

How to prevent dust build-up

Dust is usually a product of poor housekeeping, so by taking the following actions, you can reduce the risk:

• Have a regular inspection for dust build up in all areas and make sure the residue is cleaned regularly
• If you are near an ignition source, don’t use a cleaning method that will create a dust cloud, which could easily catch fire
• Maintain and empty equipment that you use regularly, such as grinders, shakers and mixers to reduce the amount of dust that comes out of those machines
• Prevent the release of dust particles from machines by using a sealant
• Make sure that there are dust collectors when your machinery is running

Preventing dust from igniting

A source of ignition could come from anything that has a source of energy, such as a flame, electricity or hot surfaces. Make sure that you do the following:

• Use vehicles, tools and welding and cutting equipment correctly
• Make sure that dust is kept away from hot surfaces or hot equipment
• Keep dust away from heat sources such as radiators or portable heaters
• Ensure that all of your equipment is maintained to avoid dust build up or overheating

To find out more about the danger of dust in the workplace, the Health and Safety Executive have produced a free-to-download guide – Safe handling of combustible dusts: Precautions against explosions.