Usage Skills and Maintenance of Toxic and Hazardous Gas Detectors
1, Pay attention to regular calibration and testing
Toxic and harmful gas detectors, like other analytical and detection instruments, use a relative comparison method for measurement: first, calibrate the instrument with a zero gas and a standard concentration gas, obtain a standard curve, and store it in the instrument. During 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 to calculate the accurate gas concentration value. Therefore, zeroing the instrument at any time and regularly calibrating the instrument are essential tasks to ensure accurate measurement. It should be noted that many gas detectors currently have replaceable detection sensors, but this does not mean that a detector can be equipped with different detector probes at any time. Whenever replacing the probe, in addition to requiring a certain sensor activation time, the instrument must also be recalibrated. In addition, it is recommended to perform response testing on the standard gas used in various instruments before use to ensure that the instruments truly provide protection.
2, Pay attention to the detection interference between different sensors
Generally speaking, each sensor corresponds to a specific gas being detected, but no gas detector can be absolutely effective. Therefore, when choosing a gas sensor, it is important to understand as much as possible the detection interference of other gases on the sensor to ensure accurate detection of specific gases.
3, Pay attention to the lifespan 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 and can be used for about three years; The lifespan of the photoionization detector is four years or longer; The lifespan of electrochemical specific gas sensors is relatively short, usually between one to two years; The lifespan of oxygen sensors is the shortest, about one year. The lifespan of electrochemical sensors depends on the drying of the electrolyte, so if they are not used for a long time, sealing them in a lower temperature environment can extend their service life to a certain extent. Fixed instruments have a relatively large volume and longer sensor lifespan. Therefore, sensors should be tested at all times and used within their effective period as much as possible. Once they fail, they should be replaced in a timely manner.
4, Pay attention to the concentration measurement range of the testing instrument
All types of toxic and harmful gas detectors have their fixed detection range. Only by completing the measurement within its measuring range can the instrument ensure accurate measurement. However, measuring beyond the measurement range for a long time may cause permanent damage to the sensor.
For example, if the LEL detector is accidentally used in an environment with more than 100% LEL, it may completely burn out the sensor. Toxic gas detectors, when used at high concentrations for extended periods of time, can also cause damage. Therefore, if a fixed instrument emits an over limit signal during use, the measurement circuit should be immediately turned off to ensure the safety of the sensor.
