EH40/2005 workplace exposure limits

The Health and Safety Executive (HSE) has published a new edition of EH40 which supercedes the previous 2011 version. The 2018 edition has been updated to include new and revised workplace exposure limits (WELs) introduced by the fourth Indicative Occupational Exposure Limit Values (IOELV) Directive. It will guide those responsible for controlling exposure to hazardous substances at work.

Many people are exposed to various substances at work, such as chemicals, fumes, dusts, and fibres, which can, under some circumstances, have a harmful effect on their health. These are referred to as ‘hazardous substances’. If exposure to a hazardous substance is not properly controlled, it may cause ill health in a number of ways. The substance may cause harm by:

• too much being taken into the body through breathing
• being absorbed through the skin
• being swallowed
• acting directly on the body at the point of contact

This edition takes account of the new limits for substances listed in Directive 2017/164/EU, the fourth Indicative Occupational Exposure Limit Values (IOELV) Directive which was implemented on 21 August 2018. Details of the changes that came into force then are summarised in EH40.

This edition also reintroduces the biological monitoring guidance values in Table 2 for chlorobenzene, isocyanates and 4,4-methylenedianiline which were omitted from the previous version.