In the below-described cases, measurements of work substances are to be carried out at regular intervals

• If a MAC (maximum allowable concentration) value or a TAC (technical approximate concentration) value have been defined for a certain substance and if its occurrence at a workplace cannot be safely ruled out,
• If an explosive (see explosive atmosphere) or a flammable work substance is used in possibly dangerous concentrations.

Measurements may only be carried out by competent staff using suitable measuring devices and equipment.

• Measurements (for Explosion Protection)
• Medical Surveillance (Regulation)