Dust

Dust comprises of small particles in the air, they are often too small to be seen but they can be breathed in through the nose and the mouth, larger particles are called inhalable dust and small particles of dust that can be inhaled deeply is called respirable dust. Very small particles can pass through the lungs into other parts of the body.

Dust can be organic or inorganic. Organic dust comes from living things and includes dust from grain, flour, textiles, wood, poultry and leather.
Inorganic dust comes from tones, metals, cement, coal, asbestos, concrete, grout and sand. The most serious health problems that arise due to dust are cancers of the lungs, throat and nose and other lung conditions called Chronic Obstructive Pulmonary Disease that includes chronic bronchitis and emphysema.

Dust is created daily in hundreds of different ways in different types of workplace, from the more obvious where stone or wood is ground and cut, flour in bakeries, to dust caused by paper shredding or toner cartridges in offices.

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 of inhalable dust or 4 mg/m³ of respirable dust as measured by a formulae that takes account of the length of time that a person is exposed, so it is the equivalent of an 8 hour day. This is called the 8 hour TWA. If any worker is exposed above these levels employers are meant to take action to remove the risk.

When assessing the risks, consider how large is the task, will a large amount of dust being created in a short space of time, the work area how enclosed is it? how long will the procedure take, the longer it takes the more dust there will be, how frequently will the procedure be taking place, the more regularly it is done the higher the risk.

To control the risk, consider whatever procedure creates the dust, take steps to control the risk by eliminating the use of any harmful substances, identify ways to stop or reduce the amount of dust created before the work starts to use a safer form of the product being used, is it possible to use a paste rather than a power? Is it possible to purchase the item pre-mixed? Contain and extract the dust near the source to limit or stop dust becoming airborne, provide free personal protective equipment (PPE) and make sure that it fits the employee correctly and that employees have received any training required to use their PPE correctly, that they know the dust controls and how to check they are working and make sure they understand about dust risks and how dust can could harm them.

Consider the use of less powerful tools or other work methods, reduce the amount of cutting required by using the right size of material so less cutting or preparation is needed. Limit the number of employees exposed to the site, rotate the employees who are doing the task.

Ordering items such as building materials in the right size will reduce the dust created by cutting and preparation, using adequate ventilation and extraction and the appropriate PPE will all help to reduce the risk posed by dust. As with any procedure or control, these should be reviewed to ensure that they are effective, workers should be supervised to ensure that they use the controls provided and equipment should be maintained.