Work substances are governed by Part Four of the Labour Protection Act (ArbeitnehmerInnenschutzgesetz, ASchG) and, in more detail, by the Regulation relating to Maximum Permissible Values (Grenzwerteverordnung, GKV of 2007) and the Regulation relating to Biological Agents (Verordnung biologische Arbeitsstoffe, VbA). Within the meaning of the Labour Protection Act, work substances are all materials, preparations and biological agents used during work. Under the Labour Protection Act, the term “used” is to be understood in a broader context and comprises (amongst other activities) also the refilling, storing and transporting of substances. Pursuant to Section 40 of the Labour Protection Act, specific requirements must be met by hazardous substances. In this context, it is important to note that hazardous substances are also subject to the provisions of the Regulation relating to Chemicals (Chemikalien-verordnung, ChemV) as well as the EU provisions of REACH (registration, evaluation, authorization and restriction of chemicals) and the Global Harmonized System of Classification and Labelling of Chemicals (GHS). See also: Assessment Period, Substitution of Work Substances Harmful to Health, Limit Values, Regulation relating to Limit Values, Wood Dust, Marking, MAC (maximum allowable concentration) values, TRC (technical reference concentration), Measurements, Safety Data Sheet, Mixtures of Substances, Effect of Substances, Ban on Circulating Air Systems, Packaging.