The principle and precautions for using a toxic and harmful gas detector
Firstly, it should be noted that toxic gas detectors are instruments and tools for detecting the concentration of toxic gas leakage, mainly referring to portable/handheld gas detectors. Mainly using toxic gas sensors to detect the types of gases present in the environment. Toxic gas detectors are not as versatile as combustible gas detectors. Toxic gas detectors are highly targeted gas detectors that are selected based on the specific toxic gas being measured. For example, carbon monoxide detector and CL2 gas detector, although both are called toxic gas detectors, are completely different toxic gas detectors because the specific gases measured are different. If a carbon monoxide detector is used to detect CL2 gas in the presence of HCL gas, the carbon monoxide detector will not react.
That is to say, carbon monoxide detectors cannot detect CL2 gas, so before selecting a toxic gas detector, it is necessary to clarify which specific type of toxic gas to test. The toxic gas detector can be selected as a pump suction type or a diffusion type based on its toxicity level. If the toxicity of toxic gases is high and there is a danger for personnel entering, a pump suction toxic gas detector must be selected. If the toxicity of toxic gases is not very high and can exist in trace amounts, but long-term inhalation can also cause danger. In this case, a diffusion type toxic gas detector can be selected, such as in places where carbon monoxide exists.
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 of 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, zero calibration of the instrument at any time and frequent calibration of 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. Whenever a probe is replaced, in addition to requiring a certain activation time for the sensor, 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. Attention should be paid to the concentration measurement range of the detection instrument: various toxic and harmful gas detectors have their fixed detection range. Only when the measurement is completed within its measurement range can it be guaranteed. Verify that the instrument accurately performs the measurement. If the measurement exceeds the measurement range for a long time, it may cause significant damage to the sensor. For example, if an LEL detector is accidentally used in an environment exceeding 100% LEL, it may completely burn the sensor. The use of toxic gas detectors at high concentrations for extended periods of time can also cause damage. Therefore, if a fixed instrument emits an overrun signal during use, the measuring circuit should be immediately closed to ensure the safety of the sensor.
