The HSE website states that COSHH (Control of Substances Hazardous to Health) is the law that requires employers to control substances that are hazardous to health. Substances can take many forms and include:
More details can be found by visiting: https://www.hse.gov.uk/coshh/basics/substance.htm or downloading: Working with Substances Hazardous to Health – a brief guide to COSHH: https://www.hse.gov.uk/pubns/indg136.pdf
The HSE website also states:
As well as controlling exposure to substances hazardous to health, you need to be aware that legal limits have been set on the amounts of many of the substances that can be present in workplace air. These are known as workplace exposure limits (WELs). They are listed in HSE’s booklet: EH40 Workplace Exposure Limits - Containing the list of workplace exposure limits for use with the Control of Substances Hazardous to Health Regulations 2002 (as amended): https://www.hse.gov.uk/pubns/priced/eh40.pdf
The HSE continues: If the substance is known to cause cancer or asthma (check the label/safety data sheet), you must control exposure to as far below the level as is reasonably practicable
Workplace Exposure Limits (WELs): https://www.hse.gov.uk/coshh/basics/exposurelimits.htm
Exposure to isocyanates found in products including polyurethane paints and coatings can cause respiratory diseases including occupational asthma, whilst conventional solvent-based paints can cause irritation of the eyes, nose and throat.
The EH40 publication advises that Isocyanates (all (as –NCO) except methyl isocyanate) have a long-term exposure limit (8-hr TWA reference period) of 0.02mg/m³ and a short-term exposure limit (15-minute reference period) of 0.07mg/m3.
A number of useful information sheets containing advice on how to minimise risks associated with paint-spraying can be downloaded from the HSE website.
SMART paint spraying – how to control health and safety risks: https://www.hse.gov.uk/pubns/indg473.pdf
Isocyanate Paint Spraying – safely managing spray booths and rooms: https://www.hse.gov.uk/pubns/priced/hsg276.pdf