Service life of portable gas detectors and other points for attention
Portable gas detectors are the new favorite of gas detectors. With the maturity of gas detection technology and continuous progress, portable gas detectors can be equipped with multiple gases (inorganic/ Organic) sensor to realize the detection of single gas and multiple gases. The portable gas alarm has the characteristics of small size, light weight, fast response, and multi-gas concentration display at the same time.
A. Pay attention to regular calibration and testing during the use of portable gas alarms
At present, many gas detectors can replace the detection sensor, but this does not mean that a detector can be equipped with different detector probes at any time. Whenever the probe is changed, the instrument must be recalibrated in addition to the sensor activation time. In addition, it is recommended to test the response of the standard gas used for the instrument before using it to ensure that the instrument really plays a protective role. Combustible gas alarms and toxic gas alarms, like other analytical and testing instruments, are measured by relative comparison method: first, a zero gas and a gas with a standard concentration are used to calibrate the instrument, and the standard curve is obtained and stored in In the instrument, when measuring, the instrument compares the electrical signal generated by the gas concentration to be measured with the electrical signal of the standard concentration, and calculates the accurate gas concentration value. Therefore, zeroing the instrument at any time and frequently calibrating the instrument are essential tasks to ensure the accuracy of the instrument measurement.
B. Pay attention to the detection interference between various sensors
Although the composite gas detector can detect a variety of other gases at the same time, the portable gas detector is not any combination of toxic and harmful gases. Generally speaking, each gas sensor corresponds to a specific detection gas, but any gas detector cannot be absolutely specific. Therefore, when selecting a gas sensor, it is necessary to understand the detection interference of other gases to the sensor as much as possible, so as to ensure its accurate detection of specific gases.
C. Pay attention to the life of each portable gas alarm sensor
All kinds of gas sensors have a certain service life, that is, life. Generally speaking, in portable instruments, LEL sensors have a longer lifespan, generally about three years; photoionization detectors have a lifespan of four years or longer; electrochemical specific gas sensors have a relatively short lifespan, generally In one to two years; the life of the oxygen sensor is the shortest, about one year or so. The life of the electrochemical sensor depends on the dryness of the electrolyte, so if it is not used for a long time, sealing it in a lower temperature environment can prolong its service life. Due to the relatively large size of the fixed instrument, the life of the sensor is also longer. Therefore, it is necessary to test the sensor at any time, use it within the validity period of the sensor as much as possible, and replace it in time if it fails.
D. Pay attention to the concentration measurement range of the gas detection instrument
Portable gas detectors have fixed detection ranges for various types of toxic and harmful gas detectors. Only when the measurement is completed within its measurement range can the instrument be accurately determined. If the measurement is performed beyond the measurement range for a long time, it may cause permanent damage to the sensor. For example, if an LEL detector is accidentally used in an environment with more than 100% LEL, it may completely burn the sensor. As for the toxic gas detector, it will also cause damage if it is used at a higher concentration for a long time. Therefore, if the fixed instrument sends an over-limit signal during use, the measurement circuit should be turned off immediately to ensure the safety of the sensor.
