Precautions for Using Toxic‑Hazardous Gas Detectors
① Perform regular calibration and testing Like other analytical instruments, toxic‑hazardous gas detectors work based on relative comparison. The instrument is calibrated with zero‑gas and standard‑concentration gas, and the calibration curve is stored inside. During measurement, the electric signal generated by target gas is compared with that from standard gas to calculate accurate concentration values. Therefore, frequent zero‑point adjustment and periodic calibration are essential to guarantee measurement accuracy.
Note: Many gas detectors support sensor replacement, but this does not mean one detector can arbitrarily be fitted with different sensor probes. Whenever a probe is replaced, sufficient sensor warm‑up time is required and full recalibration must be carried out. It is also recommended to conduct a response test with standard gas before use to ensure the instrument provides effective safety protection.
② Be aware of cross‑interference among different sensors Generally, each sensor is designed for one target gas, yet no gas sensor is completely specific. When selecting a sensor, learn about possible interference from other gases to ensure reliable measurement of the target gas.
③ Pay attention to sensor service life All gas sensors have a limited service life. For portable instruments: ‑ LEL sensors: approximately 3 years
‑ Photoionization (PID) sensors: 4 years or longer ‑ Electrochemical specific‑gas sensors: 1‑2 years ‑ Oxygen sensors: roughly 1 year (shortest lifespan)
The service life of electrochemical sensors depends on electrolyte consumption. Sealed storage in a cool environment can extend service life if the instrument remains idle for long periods. Fixed‑type detectors have relatively longer sensor service life due to larger physical size. Sensors shall be inspected regularly, used within their valid period and replaced promptly once they fail.
④ Observe the measuring range of the detector Every toxic‑hazardous gas detector has a fixed measuring range. Accurate results can only be obtained within this range. Long‑term over‑range measurement may cause permanent damage to the sensor.
