Instrument Selection: Selection Criteria for Toxic and Harmful Gas Detectors

Different types of places require different requirements for safety and hygiene. In some places, the gas content is a very important indicator. It will affect the safety of workplace workers and explosion protection requirements. Therefore, All companies and government inspections need to have a toxic and harmful gas detector ready to monitor the gas conditions at the site. The following is a brief introduction to the selection method for toxic and harmful gas detectors.

First, the location of the gas detector must be determined.

In different places, the type of gas to be tested is also different. Some areas are explosion-proof areas, the detector also requires explosion-proof equipment. In some places where it is not easy for staff to enter or exit, online gas detection equipment is recommended.

The second step is to confirm that the type of gas to be detected and its respective concentration require different types of gas. According to the influence of the gas, there will be different concentration requirements. In some locations, if there is only a gas leak, the lower limit sensitivity of the instrument is higher.

Gas detectors, the most used are two types, one is a portable gas detector, and the second is a fixed (online) gas detector.

Most of the companies nowadays use portable gas detectors. This type of instrument is small in size and easy to handle. It can be carried to different locations for detection. Electrochemical principle detectors are used. Generally, batteries can be used continuously for thousands of hours. The battery can also be recharged. Widely used by large enterprises. However, it also has its shortcomings. First, it does not measure continuously. For example, some companies only measure once a day. This does not truly reflect the actual gas content of the entire day. Disadvantage 2: Mobile design can easily cause the acceleration of the inherent error of the instrument's electronic components. It needs to be calibrated more frequently. Otherwise, the accuracy of measurement is doubtful. Disadvantage three: Battery voltage and current, there will be fluctuations or weakening, measurement results will have an impact. Disadvantage 3: In some production sites, portable detectors are not easy to detect.

For stationary (online) gas detectors, the shortcomings of portable gas detectors can be well overcome. On-line gas detector, which is a gas detection instrument fixedly installed in a certain production site, is generally composed of a sensor, a cable and a transmitter. The transmitter can transfer the measurement value to the real-time display value on the control system such as PLC or DSC through the analog quantity, and save the measurement data. In some confined spaces, such as infusion pipelines, reactors, liquid distribution tanks, centrifuges, etc., the content of certain gases needs to be detected. Therefore, only on-line gas detectors are used. The biggest disadvantage of on-line gas detectors is the high cost of initial investment, of course, the level of cost, it depends on the use of part to properly consider its true value lies.