Three Important Notes on Operation of Portable Gas Detectors
Portable gas detectors are widely applied in petrochemical industry, industrial production, flue‑gas and exhaust‑gas environmental monitoring, sewage treatment, biopharmaceuticals, household environmental protection, school laboratories and other fields. They feature fast response, good stability, high sensitivity, compact size, light weight and easy portability. Equipped with a built‑in gas sampling pump, they deliver more accurate and rapid measurement results.
When operating portable gas detectors, users shall pay attention to the following three points:
① Pay attention to the measuring range of the portable gas detector.
Every gas detector has a fixed detection range. Accurate measurement can only be achieved within this range; otherwise, the reading will be much lower than the actual environmental concentration. Furthermore, long‑term over‑range measurement will damage the sensor, resulting in incorrect readings even within the normal measuring range afterwards.
② Pay attention to the service life of the sensor inside the gas detector.
All gas detectors have limited service life, and portable gas detectors are no exception. Sensors will age even if the instrument is not frequently used. Generally speaking, among portable gas detectors, photoionization sensors have the longest service life of approximately four years. LEL sensors rank second with a service life of more than three years. Electrochemical specific‑gas sensors have a relatively shorter lifespan, normally one to two years. Oxygen sensors can only work for around one year.
Therefore, read the instruction manual carefully before use. Operate the instrument within the valid period of the sensor. Replace the sensor immediately once it expires.
③ Perform 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, and store the calibrated standard curve inside the instrument.
② Compare the electrical signal generated by the standard‑concentration gas with the electrical signal generated by the target‑gas sample, and calculate to obtain the accurate gas‑concentration value.
