DANGERS OF DUST GUIDE
Many work activities can create dust, and exposure to any dust in excessive amounts can create respiratory problems.
Dust can be a problem in almost any industry. The hazards of dusts like silica and wood are well recognised, and HSE produces specific guidance for these dusts, but there are many more substances that generate dusts which are hazardous to health. Exposure to all such dusts needs to be prevented or, where this is not reasonably practicable, adequately controlled.
Many work activities can create dust. Some examples are:
- filling bags or emptying them into skips or other containers;
- weighing loose powders;
- cutting, eg paving stones;
- sieving and screening operations;
- conveying materials by mechanical means or by hand;
- stockpiling large volumes of processed materials;
- crushing and grading;
- milling, grinding, sanding down or other similar operations;
- cleaning and maintenance work;
- feeding livestock from bags or conveyor systems;
- clearing up spillages.
Some simple checks may help in identifying whether a problem exists:
- Is the material naturally dusty?
- Does the work you do create dust by mechanical or other means?
- Is dust liable to be disturbed?
Visible dust on pipes, surfaces, ledges etc may indicate the presence of airborne dust. However, many dust particles are too fine to be visible under normal lighting conditions. A dust lamp, which provides a powerful beam of light, can be used as a quick method to show whether a fine dust is present, and helps to pinpoint the sources and movements of such dust.
What are the effects on health?
- Exposure to any dust in excessive amounts can create respiratory problems.
- The harmful effects of dust can vary, from skin irritation to lung cancer,
depending on the composition of the dust and the type and degree of exposure.
Dust is not always an obvious hazard because the particles which cause the most damage are often invisible to the naked eye and the health effects of exposure can take years to develop.
Dust that can enter the nose and mouth during breathing is referred to as ‘total inhalable dust’. Some dust may consist of larger or heavier particles that tend to get trapped in the nose, mouth, throat or upper respiratory tract where they can cause damage.
Dust particles that are small enough to be breathed into the lungs are called ‘respirable dusts’; these dusts can build up in the air spaces in the lungs and can lead to lung damage.
The build up of any dust in the lungs could produce lung damage with inflammation and eventually fibrosis (scar tissue). This could lead to breathing impairment. These conditions usually develop slowly, so symptoms may not appear until severe irreversible changes have taken place.
Some dusts are well known for their ability to produce serious lung diseases of this type, eg respirable crystalline silica (RCS) can cause silicosis and also lung cancer. Chronic effects of dust in the lungs are usually permanent and may be disabling, so prevention of the onset of disease should be given the highest priority.
Certain dusts, eg dusts from grain, flour, wood, reactive dyes and proteolytic enzymes are respiratory sensitisers which can cause occupational asthma (attacks of coughing; wheezing and chest tightness), rhinitis (runny or stuffy nose) and extrinsic allergic alveolitis (symptoms can include fever, cough, worsening breathlessness and weight loss).
Some dusts can cause ulceration of the skin and irritation or skin sensitisation can be caused by dusts such as epoxy resins, rubber processing chemicals, wood dust and fibreglass and can lead to dermatitis.
Dust particles produced during the cutting, grinding and drilling of materials can cause eye damage/irritation, and some dusts may cause eye damage/irritation due to their chemical nature.
Some inhaled dusts can become trapped in the mucus that lines the respiratory tract. This mucus tends to be either spat out or swallowed. Inhaled dusts can get into the digestive tract, where they can cause local effects such as gastrointestinal tract irritation. Alternatively, they can enter the bloodstream and produce effects in other organs and tissues.
Dusts may also find their way into the digestive tract via hand-to-mouth contact so ensure that employees maintain good standards of personal hygiene, and consider whether eating and drinking should be prohibited in the workplace.
The COSHH Regulations require employers to assess the risk to their employees, and to prevent or adequately control the exposure of employees to substances hazardous to health. You should:
- make a suitable and sufficient assessment of the risks to health from the dust(s) concerned and of the steps that need to be taken to meet the requirements of COSHH; and
- implement those steps before the work begins.
Sometimes air sampling may be needed to find out the level of exposure. These measurements should be made under normal working conditions and may be supported by the observation of light scatter by using a dust lamp to detect any less obvious escapes of very fine dust.
A risk assessment should include:
- an assessment of the risks to health from dust which should include:
- – information on the hazardous nature of the dust;
- – the type of exposure (inhalation, dermal or ingestion);
- – how the exposure occurs;
- details of the controls to be used; and
- if appropriate, arrangements for emergency procedures.
If you employ five or more people, the significant findings of the assessment must be written down, along with the steps you are taking to prevent or control exposure.