The negative impact brought by the development of industrialization requires the supervision department to strengthen management

With the development of industrialization, toxic and harmful gases have become a dangerous source that we must not face in production and life. Including petrochemical enterprises, chemical industry, environmental emergency incidents, terrorist attacks, storage and transportation of dangerous goods, landfills and even urban sewage treatment, various types of underground pipelines, etc., we may be unknowingly threatened by dangerous gases .

The people-oriented concept requires us to care about our health and safety anytime, anywhere, and various leaks and explosions continue to cause social crises and the destruction of public property. However, the detection of various types of gas is always a complicated task, and it is more difficult to choose a suitable gas monitor. Based on ISC (IndustrialScientific) 's decades of experience in gas detection around the world (including China), we have compiled this selection guide to enable readers to understand the various sensing technologies used for gas monitoring. The introduction of different types of instruments will help users choose the most suitable gas monitor.

At present, the more common types of gas sensors used for on-site detection include: electrochemical sensors, infrared sensors, catalytic combustion sensors, photoionization detectors, solid-state sensors, semiconductor sensors, etc. All gas sensor technologies rely on the physical or chemical properties of the gas itself to convert it into electrical signals that can be processed, amplified, and transmitted by electronic circuits through photoelectric technology. Therefore, as a relative detection technique, all gas monitoring instruments must often be calibrated with standard concentrations of gas. At the same time, although the manufacture of these sensors is becoming more and more sophisticated, they will not be able to meet the performance indicators of analytical instruments due to the limitations of their own principles, and it is difficult to use them as gas quantitative analyzers. Do indicate whether the location is safe or not. In any case, the relevant gas concentration provided by such sensors will still play an important role in safety, environmental protection and public health. As an on-site safety instrument, this type of gas monitor will detect the concentration value in real time when harmful gases are present, and when it exceeds a certain limit, it will immediately issue an alarm to guide people's actions. In order to adapt to different uses, this type of instrument generally adopts a portable or fixed type, which has the characteristics of simple operation, convenient maintenance, and reasonable price.

So far, there is no gas sensor with special effects on certain gases. If higher selectivity is required, use analytical instruments. There are many analytical instruments used for gas monitoring, such as: Fourier transform infrared, gas chromatography and mass spectrometry. These instruments can provide the most accurate and highly selective gas concentration data. However, they are generally relatively expensive, and are not suitable for on-site gas monitoring due to high maintenance cost, long response time, large volume, cumbersome operation, and cannot reflect the on-site concentration immediately. As laboratory gas monitoring instruments, they often serve as the final judge.

The detection of hazardous gas is a systematic management project. We need to determine the gas to be detected on the basis of recognizing the occurrence, development and existence of various harmful gases, and select the appropriate detector to ensure the safety of various personnel and industrial and mining enterprises. Confined spaces (including reaction tanks, oil tanks, workshops lacking good ventilation, underground pipelines, underground drainage ditches, underground storage tanks, cabins, etc.) are important places that require hazardous gas detection. Anyone who is about to enter or has entered a confined space for work must constantly monitor the concentration of toxic and harmful gases in the workplace, and these dangerous components may exist before workers enter the confined space, or because of them Activities in between are formed. The vast majority of accidents occur due to the lack of detection of hazardous gases before and during the work of workers in confined spaces.

Petrochemicals and other chemical companies are common places where toxic and harmful gases exist. From the raw materials, production process, product storage and transportation, flammable and explosive gases, toxic and harmful gases occur and leak. With the widespread application of industrial products, the handling of environmental emergency accidents is also increasingly placed in front of governments at all levels and accident handling teams. How to monitor the toxic and harmful gases before the accident, track the toxic and harmful gases during the accident, and detect the environment and personnel residues after the accident, this is also the most basic of gas monitoring instruments in environmental emergency accidents application.