Occupational Exposure Limits
An occupational exposure limit is an upper limit on the acceptable concentration of a hazardous substance in workplace air. It is typically set by competent national authorities and enforced by legislation to protect occupational safety and health. However, in an attempt of harmonization at EU level, the European Commission has established three types of limit values:
- Indicative Occupational Exposure Limit Values (IOELV)
- Binding Occupational Exposure Limit Values (BOELV)
- Biological Limit Values (BLVs)
The formal procedure for developing EU OELVs can be found at the ECHA website.
While IOELVS are health-based, non-binding values, BOELVS take account of socio-economic and technical feasibility factors. Therefore, when setting a BOELV policy considerations are of major importance. For any chemical agent for which an indicate OEL value is established at EU level, Member States must establish a national exposure limit value, taking into account the Community indicative limit value, determining its nature in accordance with national legislation and practice. For a chemical agent with a BOELV, Member States must establish a corresponding national binding OEL value which can be stricter, but cannot exceed the Community limit value. Exposure limit values for each country should be checked for in the national legislation.
A number of glycol ethers have IOELVs established for them, which are listed below:
|Directive||Substances||CAS Number||8hr TWA||15 min STEL||Notation|
*The indicative OELs for EGME and EGEE will become binding OELs as both are part of 12 reprotoxic substances that are transferred to the carcinogens and mutagens directive. The directive will therefore be renamed the carcinogens, mutagens and reprotoxic substances directive, or CMRD.
EU Council press release: EU strengthens protection of workers from dangerous chemicals (3 March 2022)
BLVs are reference values for the evaluation of potential health risks in the practice of occupational health. They are established on the basis of currently available scientific data. Exposure concentrations equivalent to the BLV generally do not affect the health of the employee adversely. An overview of established BLVs for glycol ethers is given below:
|SUM||Substances||BLV||Date of adoption|
|8 mg methoxyacetic acid/g creatinine in urine (end of work-week after at least 2 weeks at work)||September 2006|
|50 mg 2-ethoxyacetic acid/l urine (40 mg 2-ethoxyacetic acid/g creatinine)||August 2007|