Using the Drager sampling system, hazardous substances in the air are collected using a suitable medium via adsorption or chemisorption.

In active sampling, the air to be evaluated is drawn through a sampling tube such as Activated Charcoal and Silica Gel tube types with a pump and passive sampling is performed with diffusion samplers like the Dräger ORSA or the Dräger Nitrous Oxide diffusion samplers.