Introduction to several precautions when using gas detectors such as LEL detectors
At present, with the development of manufacturing technology, portable multi gas (composite) detection instruments are also a new choice for us. Due to the fact that this detection instrument can be equipped with multiple gas (inorganic/organic) detection sensors on a single host, it has the characteristics of small volume, light weight, fast response, and simultaneous display of multiple gas concentrations. More importantly, the price of the pump suction composite gas detector is cheaper than that of multiple single diffusion gas detectors, and it is also more convenient to use. It should be noted that when selecting such detection instruments, it is best to choose instruments with separate switch functions for each sensor to prevent damage to one sensor from affecting the use of other sensors. At the same time, in order to avoid blockage of the suction pump due to water ingress or other reasons, it is also safer to choose an instrument with an intelligent pump design that has a pump stop alarm.
1) Pay attention to regular calibration and testing.
Toxic and harmful gas detectors, like other analytical and detection instruments, are measured using a relative comparison method: first, the instrument is calibrated with a zero gas and a standard concentration gas, and the standard curve is stored in the instrument. During the measurement, the instrument compares the electrical signal generated by the gas concentration to the electrical signal of the standard concentration, and calculates 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 can currently replace their detection sensors, but this does not mean that a detector can be equipped with different detector probes at any time. At any time, when replacing the probe, in addition to requiring a certain amount of sensor activation time, the instrument must also be recalibrated. In addition, it is recommended to conduct response testing on the standard gas used in various instruments before use to ensure that the instruments truly play a protective role.
2) Pay attention to the detection interference between different sensors.
Generally speaking, each sensor corresponds to a specific detection gas, but no gas detector can be absolutely effective. Therefore, when selecting a gas sensor, efforts should be made to understand the detection interference of other gases on the sensor, in order to ensure its 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, their 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 one to two years; The lifespan of oxygen sensors is the shortest, approximately one year. The lifespan of an electrochemical sensor depends on the drying 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 longer lifespan due to their relatively large volume. Therefore, sensors should be tested at all times and used as much as possible within their validity period. If they fail, they should be replaced in a timely manner.
