Abbreviation for “technische Richtkonzentration” (similar to PEL - permissible exposure limit) Limit value for health protection in workplaces where the occurrence of toxic substances is likely.

The concept of “technische Richtkonzentration” (transl. technical guidance concentration level) refers to the guidance concentration of gasses, vapor, aerosols, or airborne contaminants that is used as a basis for any protective measures and metrological monitoring.

TRK values are only defined for substances, for which no MAK value exists (i.e. no maximum workplace concentration has been defined on the basis of toxicological and occupational health aspects). Compliance with TRK will reduce the risk of impairment to health but will not rule out the risk completely.