The portable sampling system PSS‑STS is used to determine the total mercury concentration in flue gases. The flue gas is actively drawn from the process via a sample probe and passed through the sorbent traps. The downstream cooler, which separates the condensate, and the control unit are housed in two impact‑resistant cases (IP42). The control unit contains a front‑panel PC for monitoring and controlling the sampling process, including automatic leak tests. After completion of the sampling process, the traps are sealed and analyzed in a laboratory. New traps are used for each subsequent measurement.