Isocyanates

Risk Assessment

Health and safety regulations require employers to carry out an assessment of the risks to the health from hazardous substances present in the workplace. A suitable and sufficient risk assessment is required wherever exposure to isocyanates is likely to occur.

Where there are five or more employees a written copy of the risk assessment should be provided and employees should always be informed of any significant findings from the assessment process.

Understanding when employees and others may be exposed to isocyanate is important when conducting a risk assessment. All potential sources of exposure should be identified as well as who is likely to be exposed, and for how long.

In workplaces, the following circumstances may lead to unnecessary exposure to isocyanates:

• spraying of isocyanate containing paints
• pouring of isocyanate containing binders to make moulds and resins
• use of isocyanate containing primers, adhesives and resins for a variety of purposes
• manufacture of polyurethane rubber, foam and plastics

When identifying and assessing the risks from tasks involving isocyanates, the following structure may be helpful:

• Who – think about employees. Who is using products containing isocyanates? Is anyone else likely to be around who might be affected by the work they are doing? This might include members of the public.
• What – which product is being used? Isocyanates can be found in a number of products including polyurethane paints, coatings, foams, glues and flooring. Isocyanates also come in different forms, some of which are more volatile than others, meaning they more easily release vapours that can be breathed in.
• How – think about how the work will be done. The more spray / mist that is made the greater the risk. Spraying tasks can produce very high exposure to isocyanates.
• Where – the more enclosed the space, the greater the risk may be.

Certain activities such as spraying isocyanate based paints can create mists and aerosols containing high concentrations of isocyanates. The Health and Safety Executive have a series of videos showing how exposure occurs in paint spraying.

An example risk assessment for a motor vehicle repair body shop shows the kind of approach a small business might take when considering isocyanates as an occupational health hazard.

This template should be used only as a guide to completing a risk assessment. As every business is different, employers should carefully think through the hazards and controls unique to their work activity.

Further information on how to conduct a risk assessment is available within the HSE publication A step by step guide to COSHH assessment.