Biological Limit Values BLV

The biological limit values, according to directive 98/24/EC, are intended as binding limit values similar to the binding occupational limits for air exposure (BOELV) discussed in the previous Section. They have to be brought into force by the member states. National values must not exceed the community values. 

At present, only one biological limit value has been set in Europe. For lead and its ionic compounds a level of 70 pg/100 mb blood has been determined (aimex II to directive 98/24/EC). Medical surveillance is required if the lead level in blood is greater than 40 pg/100 mb or if the concentration of lead in the air has been found to exceed 0.075 mg m, calculated as a time-weighted average over 40 h per week. 

Though there exists only one single biological occupational limit value, in many European member states limit values have been set on a national basis. In Germany, as an example, the technical rule for hazardous substances TRGS 905 contains biological limit values (called BAT values) for 51 chemical substances [6-50]. 

This directive asserts that the following agents and work activities present a specific risk for this group of employees (listed in annex I to directive 92/85/EEC)  

EEC (see Section 6.2.3), as far as they are known to present a specific risk 

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