Bryan Bates, Sieger Gasalarm
The vast majority of hydrogen sulfide monitoring systems historically use the solid state, semiconductor, metal oxide film type sensor. This type of H2S sensor has some inherent traits which manifest themselves in the field as application problems. Examples of these application problems include lack of repeatability (span drift), partial or total loss of response with removal of power, frequent and complicated calibration requirements, desensitization with exposure to moisture and the need to subject the sensors to H2S gas between calibrations to prevent them from "going to sleep". The following is an in-depth explanation as to how and why these problems occur along with the hows and whys behind a recommended solution.