Choosing the appropriate dust extraction equipment isn’t a simple task: there are many different types of dust caused by industrial processes that can lead to serious health issues for employees.
Classified as respirable or inhalable, the dusts are extremely hazardous when workers breathe them in. Particles can enter the upper and lower respiratory tract, causing health problems such as COPD and asthma.
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In addition, some types of dust are combustible, so the resulting flammable dust can also cause a fire or an explosion. This can have potentially disastrous consequences such as loss of life or the destruction of the business premises.
It’s not hard to see why dust extraction systems are vital in the workplace, particularly around industrial equipment and processes.
As well as protecting workers’ health, it’s also important to stay within the law. The Control of Substances Hazardous to Health (COSHH) governs health and safety in the workplace.
The Health and Safety Executive can hand out fines of many thousands of pounds to any business that is not using dust filtration systems at all or using a system that is ineffective.
Choosing the right dust control equipment requires knowledge, expertise and experience, due to the various design considerations for each application.
There are two types of filtration equipment on the market. Both wet and dry dust extractor systems can be used in the workplace and it’s important to determine which one best fulfils your requirements.
Dry dust collection
Most commonly used, dry dust collectors include cyclone collectors, which separate larger dust particles from air using centrifugal force; shaker filters, which use bag filters to collect dust and a shaker mechanism to dislodge dust and clean filters; and cartridge filters, which use high volume pleated filter cartridges, and clean filters using a pulse of compressed air.
Ideal for collecting heavy dusts, these units (with the exception of cyclones) use elements made from permeable filter media. They function by using the four major components of membrane filtration: interception, impaction, diffusion and electrostatic attraction.
Additionally, some units are made as simple barriers without a cleaning system, known as static filters.
Wet dust collection
Wet dust filtration systems use a combination of water and air pressure to remove dust from the air and drive it though a water spray or stream – the dust itself is separated by gravity and settles at the bottom of the tank.
This approach provides very effective filtration at larger particle sizes. It can also help minimise the risk of fire or explosions as a result of dust being wetted during the filtering process.
Wet dust collectors tend to be used more selectively. They generally manage processes that involve combustible dust.
Dry vs wet dust collection
When you’re deciding whether to use dry or wet dust extraction, ask yourself how heavy and combustible is the dust in your work environment?
If you’re working with light and highly combustible dust, such as aluminium or titanium, you could need a wet dust extractor. Dry dust collection can be applied to these materials, but explosion relief should be considered.
Dry filtration is the standard type of filtration system in industry, while wet filters are normally used to extract flammable and explosive dusts, including titanium.
Selecting the most effective dust control solution is vital to the smooth running of your business and the safety of your employees.
A self-contained workbench with built-in dust and fume extractor systems; the downdraught bench is a popular choice.
Employees work on the surface of the downdraught bench and any dust and fumes are sucked down through the extraction bench’s surface into internal filters. The clean air is then returned to the room.