Gas Chromatograph

A gas chromatograph for analyzing a gas mixture (1) comprising:

• at least one separation column (4, 6) for separating components of a sample of the gas mixture (1) which is fed through the separation column (4, 6) by a carrier gas (3);
• a thermal conductivity detector (5, 7) which has a sensing element (5′, 7′) arranged downstream from the separation column (4, 6) and which further is adapted to detect the separated components in a non-destructive manner and to generate a detector signal (S5, S7) in response to each of the detected components;
• and
• an evaluation unit (23) for evaluating the detector signals (S5, S7) to determine the concentrations of the detected components;
• said gas chromatograph further comprising:
• at least one further thermal conductivity detector (11, 12) which has a further sensing element (11′, 12′) arranged immediately downstream or upstream from the thermal conductivity detector (5, 7) and which is adapted to detect the separated components and to generate a further detector signal (S11, S12) in response to each of the detected components;
• and
• the evaluation unit (23) being further adapted to compare the detector signal (S5, S7) with the further detector signal (S11, S12) to recognize and signal a loss of or improper detection by the thermal conductivity detector (5, 7).