Polyurethane products, such as foams, elastomers, adhesives and paints, use isocyanates as a raw material. Isocyanates can severely impact the health of those who work with them, as they’re classified as potential human carcinogens and are one of the leading causes of occupational asthma in the UK.
Pragma and Associates
Pragma and Associates explain that health effects related to isocyanate exposure can include lung problems and irritation to the eyes, nose, throat and skin. Symptoms can include chest tightness, difficulty breathing and inflammation of mucous membranes and skin.
People can become sensitised to isocyanates, which can trigger an asthma attack even with low-level exposure. This can be via inhalation and skin contact.
Exposure in the workplace can occur from a variety of processes. Routine tasks, such as painting, varnishing, foam-blowing, the manufacturing of insulation materials (e.g. car seats, furniture, mattresses) and adhesive application, can lead to isocyanate exposure.
The UK and many other countries have set Workplace Exposure Limits (WEL) for isocyanates. In the UK, airborne concentrations should be kept below the WEL and to a level that is as low as reasonably practicable.
We recommend the following steps for any substance deemed hazardous to health:
- Assess the risks and inform the appropriate people.
- Prevent, or where this is not reasonably practicable, adequately control exposure.
- Maintain and check control measures.
- Check the efficacy of control measures through air monitoring and health surveillance.
- Provide information, instruction and training.
- Make plans for accidents and emergencies.
Your risk assessments for processes involving isocyanates should be completed by a competent person, include comments on the following and, where appropriate, outline reasons why further control measures cannot be implemented:
- Can the isocyanates be eliminated from the process?
- Can the isocyanates be substituted for an alternative substance that is less hazardous?
- Can further engineering controls be used? These can include total or partial enclosure of the process with local exhaust ventilation.
- Can further administrative controls be used? These can include reducing the exposure duration (time limits or rotating staff) and improving the training provided to appropriate people on the health effects and control measures.
- Does personal protective equipment (PPE) or respiratory protective equipment (RPE) need to be used?
Having a competent person undertake an industrial hygiene assessment, including air monitoring, can help you ascertain the level of control of isocyanates in your workplace. Air monitoring results should be included in your risk assessment.
You should keep maintenance and service records. Biological monitoring and health surveillance should be considered.
Pragma and Associates has decades of experience in controlling exposure to isocyanates and have helped workplaces to prevent occupational ill-health and comply with the relevant legislation.