Workplace Exposure Limits

In 2005, a simpler occupational exposure limit system came into force. The old system of Maximum Exposure Limits (MELs) and Occupational Exposure Standards (OESs) was replaced with a single type of limit, known as the Workplace Exposure Limit (WEL). A WEL is the maximum concentration of an airborne substance averaged over a reference period that an employee may inhale. HSE guidance says that: “WELs should not be considered a hard and fast line between safe and unsafe”.

In 2011, the Workplace Exposure Limits were amended, resulting in 19 new or amended entries for substances, to comply with the European Commission’s Third Directive on Indicative Occupational Exposure Limit Values (2009/161/EU).

More information: HSE (EH40/2005) Workplace Exposure Limits HSE, Workplace Exposure Limits (EH40) 2011, available at: www.hse.gov.uk/pubns/books/eh40.htm

In May 2013, the TUC published a bulletin on carcinogens as part of its safety manifesto, Health and safety — Time for change campaign. This sets out that around 300,000 people are diagnosed with cancer in the UK every year, and that every year more than 150,000 people die from the disease. It estimates that of these around 20,000 cases a year and 15,000-18,000 deaths, are work-related and it says that all occupational cancers are avoidable.

It points out that there is no safe exposure limit for any carcinogen and even levels well below the Workplace Exposure Limits (WELS) can lead to some workers developing cancer. And it says that the aim should be to remove all exposure to any known or suspected carcinogen in the workplace.

“We should not accept levels which will continue to lead to workers developing avoidable cancers just because either the European Commission or HSE has decided that this level is ‘acceptable’, it says. Carcinogens in the workplace can be eliminated by changing processes, substituting for other substances or, where that is not possible, ensuring that levels be reduced as low as possible and workers fully protected from any contact with a cancer-causing agent.

Examples of where a cancer-causing agent cannot be removed, but exposure by a worker to any risk can be removed, are radiographers and radiation, quarry workers to silica and bus mechanics to diesel exhaust.

Employers should only use a carcinogen if there is no reasonable alternative and they are required to remove or reduce exposure “as far as is reasonable practical”.

With regard to new substances, trade unions support the “precautionary principle” which means that if there is a reasonable possibility that a substance may cause harm then there should be a presumption that it will and therefore should be controlled.

Unions are also calling for an enforcement-led campaign by the HSE and local authorities aimed at ensuring that employers who continue to expose their workers to carcinogens are prosecuted. Exposure to a WEL is not acceptable when removal or substitution is an option.