Abbreviation for “maximale Arbeitsplatzkonzentration” (similar to threshold limit value).
The MAK value specifies the maximum concentration level of a toxic substance in air at a workplace. For example, the MAK value of 0.6 mg/m3 formaldehyde indicates that a maximum of 0.6 milligrams of formaldehyde are permissible in 1 cubic meter of air at a workplace. This is a time-weighted average value applicable for an exposure duration of 8 hours per day. The lower the MAK value of a substance, the greater its health-damaging capacity. MAK values are not permanent, they are based on the latest findings, respectively.
If for specific hazardous substances it is not possible to define MAK values on the basis of toxicological and occupational health aspects, an alternative factor, referred to as “technische Richtkonzentration (TRK) (similar to PLE - permissible exposure limit) is specified. According to the hazardous substances regulation, employers are obliged to determine whether or not hazardous substances escape into ambient air and whether the MAK and TRK limits are reached or exceeded.