Guidance on working with 2-pack isocyanate paints
Paints containing isocyanate are used extensively in MVR as almost all motor vehicle repair bodyshops use 2-pack or “2K” isocyanate-containing paints. Isocyanates are used in some water-based paints, most base coats and almost all lacquers. ‘Water-based’ does not mean ‘isocyanate-free’, just that it is emulsion based and has reduced levels of solvents.
Spraying 2-pack isocyanate paints is the main cause of occupational asthma in the UK and, for years, vehicle paint sprayers have been the group most at risk.
MVR paint sprayers have about a 90 times higher risk of getting asthma compared with the UK working population.
Every year around 50 sprayers are diagnosed with isocyanate asthma and most have to leave the industry. Other workers in bodyshops are also sometimes affected eg maintenance personnel, managers and others who work in close proximity to spray booths/rooms. This spray mist containing isocyanate may also worsen existing asthma. Once people are affected even very low exposure levels can trigger an attack. Significant skin contact with isocyanate hardeners may cause dermatitis.
Over a number of years the HSE have worked with industry representatives to explode the myths and explain why even the best air-fed visor can fail to protect people. The ground-breaking training material used at these Safety and Health Awareness Days has now been made freely available on the MVR webpages
Below are some key tips for vehicle paint sprayers and owners of motor vehicle repair bodyshops.
Vehicle paint sprayers
- The risk of developing occupational asthma occurs because paint spraying produces a lot of invisible airborne mist that you can breathe in. Never spray paint outside the booth or room.
- Your booth/room takes time to clear of mist, so know the clearance timeand make sure everyone else does too.
- Always wear air-fed breathing apparatus (BA) when spraying and know how to safely leave or enter your booth or room during the clearance time.
- Your employer should check the controls are working by measuring your exposure to isocyanate. Currently the only way to do this (and accepted by the MVR industry) is by providing a urine sample for analysis. SeeSector Information Sheet 03/2012/01 – Reducing ill health from isocyanate exposure in motor vehicle repair (MVR)
- You need regular health surveillance i.e. lung function testing and skin checks. This is to identify early symptoms and signs of occupational asthma and dermatitis (skin rashes).
Bodyshop owners / managers
- Spraying 2-pack isocyanate paints creates fine, invisible, airborne mist that can cause occupational asthma
- It spreads through the air like smoke.
- Your spray booth or room takes time to clear of fine paint mist.
- Measure the clearance time using a smoke/fog generator, clearly mark it on the entrance door(s) and make sure everyone who uses the booth/room knows what to do. For information on smoke generators and advice on how to conduct a clearance time measurement please see‘Measuring paint spray booth clearance time’.
- The research report ‘An automated system for indicating spray clearance times of MVR spray booths and rooms – RR742’ describes the design and assembly of a device consisting of a timer switch, programmed with the clearance time, which is triggered by a sensor that detects when the spray gun is turned on and off. Two types of sensor are evaluated and recommendations made for different operational setups. The system is relatively inexpensive and can be retrofitted to existing spray booths/rooms.
- Make sure the booth/room runs at slight negative pressure so that if there are any leaks, air is drawn into the booth/room rather than paint mist leaking out into the workshop
- Make a list of simple daily and weekly checks to be done in the booth/room, appoint someone to do them, record the findings and act if things are wrong
- Check exposure is properly controlled by arranging for the analysis of urine samples of vehicle paint sprayers. See Sector Information Sheet 03/2012/01 – Reducing ill health from isocyanate exposure in motor vehicle repair (MVR)
- Arrange regular health surveillance for those potentially exposed to isocyanate paints such as sprayers. For more information on health surveillance for occupational asthma see HSE guidance publication‘Health surveillance for occupational asthma (G402)’
- Use the COSHH paint spraying and allied tasks and other published advice to help you reduce exposures to isocyanates.
Information from HSE.
HSE is a vital source of information for Employers, helping to keep employees safe and employers aware of the laws relevant to their industry.