Chlorinated biphenyls (PCBs) are a group of substances for which the 2012 List of MAK and BAT Values submitted by the Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) specifies new, and in this case, significantly lower values than previously recommended. The current list, which was presented to the German Federal Minister of Labour and Social Affairs as in every year, and which is the basis for legislation on protection of health in the workplace, included new data on 94 substances. These data are based on detailed scientific research and transparent decision-making processes. The List of MAK and BAT Values is also available under open access for the first time, as are all publications of the Commission since the beginning of this year.