Limit Values European Union - IOELV and BOELV

The European Commission receives scientific advice from the Scientific Committee for Occupational Exposure Limits to Chemical Agents (SCOEL). The SCOEL consists of 21 members, who are appointed by the European Commission following consultation of the EU Member States. All SCOEL members act as independent scientific experts, not as representatives of their national governments. Their scientific expertise includes chemistry, toxicology, epidemiology, occupational medicine and industrial hygiene1.

The SCOEL aims at proposing health-based OELs when the available scientific data suggest that a clear threshold value can be identified for the adverse effects of the substance in question. For some adverse effects (in particular genotoxicity, carcinogenicity and respiratory sensitisation), existing knowledge does not enable such limits to be identified. In these cases, the SCOEL recommends a pragmatic OEL, which is established at levels considered to present a sufficiently low risk. The proposed values for a particular substance may include the eight-hour time-weighted average (TWA), short-term limits/excursion limits (STEL) and biological limit values. The OELs may be supplemented, as appropriate, by further notations.

The SCOEL assesses the most recent scientific data available for identification of the critical health effects. A short document is then written describing the recommendation for OELs and the supporting information, the critical effect, the extrapolation techniques used, and any data on possible risks to human health and the technical feasibility of monitoring exposure2.The European Commission makes the document public to interested parties with a request for health-based scientific comments and any other relevant data. Following a comments period of some six months, the SCOEL re-discusses the document in the light of the comments received and adopts the final version, which is then published by the Commission3.

Once the Commission services have received recommendations from the SCOEL, they are in a position to develop legal proposals for OELs. The Commission services then seek relevant technical and socio-economic data. Any data pertinent to the development of the proposal should be made known to the Commission services at this stage. The Commission's proposal for a legislative text is submitted to the tripartite Advisory Committee on Safety and Health at Work (ACSHW), where all interested parties have a further opportunity to contribute to the opinion adopted by the Committee. ACSHW has the task of assisting the Commission in the preparation, implementation and evaluation of all initiatives related to safety and health at work. The opinion delivered by the ACSHW is available through its minutes, and is published in the ACSHW's annual report.

Once these consultations have been completed, the Commission services finalise their preparation of a proposal to be agreed by the Commission. According to Directive 98/24/EC there are two different types of European OELs: Binding Occupational Exposure Limits (BOELVs) and Indicative Occupational Exposure Limits (IOELVs). IOELVs, which are to be taken into account in the setting of OELs by the EU Member States, are substantially more common (Directives 91/322/EEC, 2000/39/EC, 2006/15/EC). BOELVs may additionally reflect feasibility factors and generally constitute minimum hygienic standards within the EU for substances with genotoxic, carcinogenic or respiratory sensitising effects, i.e., the Member States are required to set a limit based on, but not exceeding, the value of the BOELV (Directives 98/24/EC, 2003/18/EC, 2004/37/EC). Depending on the type of OEL and the legal procedure selected, further consultation on the Commission's proposal takes place within the appropriate European Union institutions before the final adoption and publication of an OEL in the Official Journal of the European Union4.

January 2010


1 Ziegler-Skylakakis, K.: How the EU establishes exposure limits for chemicals. (p. 7)

2 Methodology for the derivation of occupational exposure limits: key documentation. Luxembourg: European Commission, 1999. (Report EUR 19253 EN. ISBN 92-828-8106-7)

3 Occupational exposure limits – Recommendations of the scientific committee for Occupational Exposure Limits to Chemical Agents 1994-97 (and updates). Luxembourg: European Commission, 1998 et seq. (loose-leaf collection, ISBN 92-828-4270-3)

4 Occupational Exposure Limits and Biological Limit Values – Introduction