Working with isocyanates

Date: 24.10.25

HSE inspectors are visiting motor vehicle repair businesses using isocyanate paints.
Occupational asthma can end careers permanently - once sensitised, even tiny amounts trigger attacks.

Are your workers protected?

Isocyanates are one of the leading causes of  occupational asthma  in the UK. Every year, vehicle paint sprayers develop this life-changing condition. Once they have it even tiny amounts of isocyanate exposure can trigger an attack, which often forces them to leave the profession completely.

Two-pack (2k) paints, coatings and lacquers,  are widely used for their durability and finish quality. However, when sprayed, these paints release invisible isocyanate-containing mist that spreads rapidly and can reach dangerous levels within minutes. 

The Health and Safety Executive (HSE) is conducting inspections of motor vehicle repair businesses that use isocyanate-containing materials. These inspections focus on ensuring proper health and safety measures are in place. This guidance will help you protect your workers, comply with legal requirements, and prepare for inspections. 

Three essential actions to stay safe:

• Always use proper spray facilities and correct respiratory protective equipment.  You must use air-fed breathing apparatus – filtering respirators will not protect you.  Never allow 2-pack (2K) paints to be sprayed outside a proper spray booth or room.
• Respect clearance times – every time.  Your spray booth needs time to clear invisible isocyanate paint mist.  Workers lifting visors too soon is a common mistake.
• Monitor exposure levels regularly.  Our legal duty under COSHH Regulation 10 requires exposure monitoring.  Biological monitoring through urine testing is HSE and industry’s recommended method.