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Construction dust is not just a nuisance - it can seriously damage workers health and some types can eventually even kill. Regularly breathing these dust particles over a long time can therefore cause life-changing lung diseases.

Every year, thousands of construction workers are made ill by exposure to dust within the workplace, this results in an increase of lung diseases such as Asthma, COPD and Cancer.

Most construction dusts contain particles of a wide range of sizes. The behaviour, deposition and fate of any particle on entry into the human respiratory system and the body response that it provokes, depend on the nature and size of the particle.

There are three main types of construction dust:

1. Silica dust – created when working on silica containing materials like concrete, mortar and sandstone (also known as respirable crystalline silica or RCS)

2. Wood dust – created when working on softwood, hardwood and wood-based products like MDF and plywood

3. Lower toxicity dusts – created when working on materials containing very little or no silica. The most common include gypsum (eg in plasterboard), limestone, marble and dolomite.

The COSHH definition of a substance hazardous to health includes dust of any kind when present at a concentration in air equal to or greater than 10 mg/m3 8-hour TWA of inhalable dust or 4 mg/m3 8-hour TWA of respirable dust. Silica and wood dusts have a much lower exposure concentration level

Hard Wood and Silica dusts are classed as respiratory carcinogens and therefore exposure to these substances can cause occupational cancer. There is usually a considerable amount of time (more than 10 years) between exposure to a carcinogen and the onset of any ill-health symptoms. In circumstances where work involves activities that lead to exposure to carcinogens, all reasonable efforts must be made to reduce exposure to levels as low as possible regardless of the measured exposure.

Respirable Crystalline Silica (RCS)

Silica is a natural substance found in most rocks, sand and clay and in products such as bricks and concrete. Silica is also used as filler in some plastics. In construction these materials create dust when they are cut, sanded, carved etc. Some of this dust may be fine enough to breathe deeply into your lungs and cause harm to your health. The fine dust is called Respirable Crystalline Silica (RCS) and is too fine to see with normal lighting. The amounts needed to cause ill health are not large, the legal exposure limit for RCS is 0.1mg/m3 (100 x less than the general dust exposure limits).

Assessing the risk from this type of exposure should take into consideration the fact that any measurements obtained require a specific sampling and analysis technique (X-ray powder diffraction) different to general dust monitoring used for wood and low toxicity dusts.

Wood Dust

Carpenters and joiners are four times more likely to get asthma and other lung diseases due to working closely with wood dust on a very regular basis.

Other conditions can also develop particularly from hardwood dust such as Cancer - particularly of the nose which is why it’s very important to be aware of the workplace exposure limits and assess your workforce on a regular basis.

The legal exposure limit for hardwood dust is 3mg/m3 and for softwood dust is 5mg/m3. For mixtures of hardwood and softwood dusts the exposure for hardwood dust of 3mg/m3 applies to all wood dusts present in that mixture.

Providing dust extraction (also known as local exhaust ventilation or LEV) at woodworking machines to capture and remove dust before it can spread is imperative.

Never sweep up or use compressed air lines as this will disturb the dust and allow it to become inhaled. Always clean up using a suitable industrial vacuum cleaner which is fitted with a HEPA filtration system.