Issues that require attention when using combustible gas detectors

    Toxic and harmful gas detectors, like other analytical detection instruments, are measured by relative comparison methods: first, the instrument is calibrated with a zero gas and a gas of a standard concentration, and the standard curve is stored in the instrument. During the measurement, the instrument compares the electrical signal generated by the concentration of the gas to be measured with the electrical signal of the standard concentration, and calculates the accurate gas concentration value. Therefore, zeroing the instrument at any time and calibrating the instrument regularly are essential tasks to ensure accurate instrument measurements. It should be noted that many gas detectors can currently replace detection sensors, but this does not mean that a detector can be equipped with different detector probes at any time. Whenever the probe is replaced, in addition to requiring a certain sensor activation time, the instrument must also be recalibrated. In addition, it is recommended that before using various instruments, the instrument should be tested for response with standard gas to ensure that the instrument truly plays a protective role.

    2. Pay attention to the detection interference between various sensors

    Generally speaking, each sensor corresponds to a specific detection gas, but no gas detector can be absolutely effective. Therefore, when choosing a gas sensor, you should try to understand the interference of other gases on the sensor to ensure its accurate detection of specific gases.

    3. Pay attention to the life of various sensors

    All types of gas sensors have a certain service life, that is, lifespan. Generally speaking, in portable instruments, LEL sensors have a longer lifespan, generally about three years; the lifespan of photoionization detectors is four years or longer; the lifespan of electrochemical specific gas sensors is relatively short, generally one to two years; oxygen sensors have the shortest lifespan, about one year. The lifespan of electrochemical sensors depends on the drying up of the electrolyte, so if it is not used for a long time, sealing it in a lower temperature environment can extend its service life to a certain extent. Fixed instruments have a relatively large volume, so the lifespan of the sensor is also longer. Therefore, the sensor should be tested at any time, and used as much as possible within the validity period of the sensor. Once it fails, it should be replaced in time.

    4. Pay attention to the concentration measurement range of the detection instrument

    All types of toxic and harmful gas detectors have their fixed detection ranges. Only by completing measurements within their detection ranges can the instrument be guaranteed to perform measurements accurately. If measurements are performed beyond the detection range for a long time, it may cause permanent damage to the sensor.

    For example, if an LEL detector is accidentally used in an environment with an LEL exceeding 100%, the sensor may be completely burned. A toxic gas detector may also be damaged if it is used for a long time at a high concentration. Therefore, if a fixed instrument sends an over-limit signal during use, the measurement circuit must be immediately shut down to ensure the safety of the sensor.