Health and Safety
Executive / Commission
Operational
Author unit / section: Manufacturing Sector
Target audience: All visiting staff, Health Unit and Local Authority Inspectors
1 Exposure to isocyanates contained in vehicle spray paints has been the biggest cause of occupational asthma in the UK for more than a decade. A number of substitute materials have been suggested but any substance that possesses similar reactive properties is likely to have adverse effects on humans. Whilst some non-isocyanate primers are available, top coats and lacquers are likely to contain isocyanates for the foreseeable future. And it is important to remember that many ‘water-based’ products still contain isocyanates.
2 A concerted HSE health campaign has been targeted at bodyshops both directly (via SHADs and inspections) and indirectly (working with intermediaries such as paint and booth manufacturers, insurance companies etc). As a result, improvements in control measures in many facilities have shown that exposure to isocyanates can be prevented and there is evidence this is already leading to a reduction in the cases of asthma.
3 It is HSE’s view that the risk assessment required under COSHH for spraying of isocyanate paints in MVR should show that monitoring is requisite under COSHH Regulation 10 (1). This view is supported by para 193(a) of the COSHH ACoP because:
4. Consequently, Regulation 10 requires monitoring to be carried out providing:
5 Biological monitoring analyses isocyanate metabolites in the sprayer’s urine, and provides a suitable practical method to check if exposure is occurring (though it won’t immediately identify the route).
6 explained the application of BM in MVR bodyshops and was endorsed by industry representatives. Since the SIM was published, the number of samples conducted has risen from an average of 200 per year to over 2000 in 2007. A number of insurance companies now require their MVR client companies to undertake BM to show that exposure to isocyanates is being controlled and there is good evidence to show that standards of control are improving as a result.7 There have been isolated examples of reluctance to giving samples and it is important that informed consent is given (see HSG 167 “Biological Monitoring in the Workplace). In all cases the Sector is aware of, when it was explained why the sample was required and assurances were given that no other checks would be conducted (e.g. for drink or drugs) agreement was obtained.
8 Employees have a duty to co-operate with their employer to enable compliance with health and safety legislation (HSW S7 b) but, in practical terms, it is not possible to force anyone to participate – in the same way, workers may refuse to wear air-fed BA or give a breath sample for spirometry. Under these circumstances, the employer will need to decide on an appropriate course of action but, ultimately, may have to remove the person from work that causes exposure.
9 Monitoring by using the results from health surveillance (e.g. spirometry) alone, would not be considered suitable, because there may be considerable delay before an effect is detected and, by the time problems are discovered, health has already been affected.
10 Given the number of routes that exposure may occur, monitoring of the individual sources would be time consuming and presents a number of challenges (e.g. how do you sample inside air-fed BA and not interfere with the integrity of the system? And how much monitoring of an individual’s behaviour is needed?)
11 Currently, there are two UK laboratories who undertake such work:
Scientific Analysis Laboratory
9 Hadfield Street
Manchester M16 9FE
Tel: +44 (0)161 874 2400
Fax: +44 (0)161 874 2468
Email: sales@salltd.co.uk
http://limsgate.saiman.co.uk
and
The Health and Safety Laboratory
Harpur Hill
Buxton
Derbyshire SK17 9JN
Contact Dr John Cocker or Dr Kate Jones
tel. +44 [0] 1298 218429
fax +44 [0] 1298 218172
email: john.cocker@hsl.gov.uk
Website: http://hsl.gov.uk
Both these laboratories use a procedure that meets the protocol laid out in
12 Excretion of the isocyanate metabolites from the body means that a urine sample taken at the end of the shift only shows exposure for that shift. Consequently, care should be taken to ensure that sampling is representative.
13 Biological monitoring for isocyanates DOES NOT provide information about a person’s health; it indicates whether exposure to isocyanates is occurring. To ensure that results are interpreted correctly and appropriate remedial action is taken, suitable explanatory information should be provided by the laboratory or health service provider administering the scheme.
14 Isocyanate in the urine does not show the route of exposure. In most cases, however, control failures have been readily identified and corrective action taken, with subsequent samples being ‘clear’.
15 SIM 03/2006/04 stated that as monitoring for isocyanate exposure in MVR using BM was new, enforcement would be likely to be advice/letter. It went on to say that, as the practice became established, the Enforcement Management Model would indicate that an Improvement Notice (IN) would be appropriate unless the employer can demonstrate by some other method that adequate control is being achieved.
16 As indicated in para 6 above, biological monitoring has increasingly become the industry norm in MVR. Inspectors may now wish to consider issuing an IN where biological monitoring is not being carried out and a draft Improvement Notice is attached. The Notice requires the use of a suitable procedure and the Schedule identifies an appropriate BM procedure as fulfilling this requirement.
17 The wording of Regulation 10 suggests that monitoring exposure is required when the risk assessment (undertaken by the employer under Regulation 6) indicates it is necessary. This raises the question about whether a Notice can be issued under Reg 10 if no assessment has been carried out or if it is inadequate (ie fails to identify the need for monitoring). In practice, when an Inspector explains how exposure to isocyanate paint mist occurs (as outlined in para 3), this should be sufficient information for the employer to reassess the risks and conclude that monitoring is required to ensure adequate control of exposure is maintained. This revised risk assessment does not need to be in writing to allow an IN to be issued under Reg 10. However, inspectors should remind the employer to record (where 5 or more persons are employed) the significant findings of the revised risk assessment as soon as practicable afterwards.
18 In the event of an appeal against an IN the Sector and/or the SG Occupational Hygienist should be able to provide evidence on
Andrew Lake, Manufacturing Sector. Requests for occupational hygiene support for visits or enforcement should be sent via Niall Evans (Team Leader for the FOD national Occupational Hygiene team).
