While using the portable gas alarm, great importance should be attached to regular calibration and detection. At present, many gas detectors can replace detection sensor. However, this does not mean that a detector can be equipped with different detector probes at will. Anyhow, in addition to a required time of sensor activation in the probe replacement, it is necessary to re-calibrate the instrument. In addition, before the use of various instruments, it is suggested that the response detection of standard gas for instrument use should be carried out to ensure that instruments are really protected.  Similar to other analysis and detection instruments, flammable gas alertor and toxic gas alertor are determined by a method of relative comparison: first, the instrument is calibrated with a zero gas and a gas with standard concentration, and the  obtained standard curve is stored in the instrument. When measuring, the instrument compares the electric signal produced by the concentration of gas to be measured with the electric signal of standard concentration, and calculates the accurate value of gas concentration. Therefore, it is essential to conduct zero-calibration of instruments at any time and calibration of instruments constantly to ensure the accuracy of instrument measurement.

As a security detection equipment, the multi-gas detector can be used to detect the concentration of flammable gas, toxic and harmful gases in the environment, which is a measuring instrument for compulsory verification that is widely applied to petroleum, petrochemical industry, aviation, chemical, chemical engineering, metallurgy and other fields. Since there are various kinds of gas detectors, which have a wide range of applications, short service life of sensor elements and large differences in performance, the performance and quality of gas detectors are directly related to the personal safety of employees on the work site as one of the guarantees of safe production. Therefore, it is an important measure to ensure personal safety and property safety by adopting scientific and reasonable detection methods for different instruments.

Carbon monoxide gas detector is mainly composed of two parts: gas detector and gas  controller. The gas detector USES imported gas sensor to detect the concentration of carbon monoxide gas, which has high precision and reliability. The gas gauge was used to detect specific carbon monoxide gas density, gas alarm controller supporting gas detector system, the detecting point, according to the gas concentration independent host and detector using wire or bus mode connection, easy to install and net, centralizedly control, many of when detecting the concentration of the gas in the environment at or above the preset alarm value, the alarm immediately send out sound and light alarm, to remind users to take safety precautions.

Pump-suction gas detectors and diffusion gas detectors have the same detection principle, which is to detect the sample gas with sensors and then convert to corresponding value through the circuit magnification to display on the screen. Flammable gases are usually detected with the catalytic combustion sensors while the toxic gases are detected by electrochemical sensors. Difference between the pump-suction gas detectors and diffusion gas detectors lies in the sampling method.

The direction of toxic gas leakage is judged according to the direction of air flow, wind direction and other specific factors when there's a massive leakage. Draft the three-dimensional flow trend map of leakage according to the density of leakage gas (greater or less than air) and the trend of air flow, then make an initial point setting scheme at the downstream side.

Detection principle of gas detector is the same as that of common detectors, but it's more suitable for the continuous, long-term and stable characteristics required by fixed detection on technology and process. The fixed gas detector should also be selected according to the type and concentration of gas in the field, and they shall be installed the most possible leakage points, for example, the most effective installation height of sensor should be selected according to the specific gravity of the specific gas.

All kinds of gas sensors have a certain durable years, namely the service life. Generally, LEL sensor has a longer service life among portable instruments, which is about three years. Service life of the photoionization detector is four years or longer. Special electrochemical gas sensors have a relatively shorter service life, which is generally one or two years. The oxygen sensors have the shortest service life, only about one year. Service life of the electrochemical sensor depends on the amount of the electrolyte, so if it not used for a long time, please put it in a sealed lower temperature environment, so as to extend its service life. As the the fixed instruments have a relatively large size , their sensors often have a longer service life. Therefore, the sensor should be inspected at any time and used as far as possible within the validity period. Once it fails, replace in time.

Safety confirmation must be made before entering the working area. After takingcorresponding safety protection measures, such as the mask, gas mask (depend onspecific application scenarios) , confirm to guarantee the safety of testersand prevent potential safety hazards, then operators can detect in the workingarea. When the gas detector gives an alarm, operators should leave the workingarea immediately and keep the detection data. After more than half-hour offorced ventilation, secondary detection and measurement can be carried outagain. Detectors should write the work site and detection results on theconfirmation form, and take full responsibility for the accuracy of thedetection data.