Three Points to Note for the Use of Portable Gas Detectors
Portable gas detectors are widely applied in petrochemical industry, industrial production, flue gas and exhaust environmental monitoring, sewage treatment, biopharmaceuticals, household environmental protection, school laboratories and other fields. Featuring fast response speed, favorable stability, high sensitivity, compact size, light weight and easy portability, they are equipped with a built-in gas sampling pump to deliver more accurate and rapid measurement results.
Operators shall observe the following three points when using portable gas detectors:
① Pay attention to the measuring range of the portable gas detector: Every gas detector has a fixed detection range. Valid measurements can only be obtained within this range; otherwise, the readings will be far lower than the actual gas concentration in the environment. In addition, long-term over-range measurement will damage the sensor, leading to incorrect readings even within the normal measuring range in subsequent use.
② Pay attention to the service life of the sensor installed in the gas detector: All gas detectors have a limited service life, and portable gas detectors are no exception. Sensors will age even if the instrument is not used frequently. Generally speaking, photoionization detectors have the longest service life of about four years; LEL sensors rank second with a service life of more than three years; specific electrochemical gas sensors have a relatively shorter lifespan of one to two years; oxygen sensors can only work for approximately one year.
Therefore, make sure to read the user manual carefully before use and operate the detector within the valid period of the sensor. Replace the sensor immediately once it expires.
③ Conduct regular calibration and testing for the detector: Portable gas detectors generally adopt the relative comparison method for measurement, as described below: ① Calibrate the instrument with zero gas and standard-concentration gas to establish and store a standard curve inside the device; ② Compare the electrical signal generated by the standard concentration gas with that produced by the gas to be measured, and calculate to obtain the accurate gas concentration value.
