What are the sampling methods for gas alarms?

What are the sampling methods for gas alarms? The gas from the gas alarm detection can be divided into toxic and combustible gas alarm, the portable gas alarm types can be divided into fixed and gas alarm, alarm for each sample they are not the same, such as a portable gas alarm According to the sampling method, it is divided into diffused gas alarm and pumping gas alarm. The number of samples collected by Gurney is divided into single alarm, two-in-one portable gas alarm, three-in-one gas detector and four-in-one. Detectors and hybrid detectors.

The sensor is the main detection component of the gas alarm, and the sensor is a device or device that can be configured to be measured and converted into usable output signals according to certain rules. The gas sensor is a sensor for detecting the composition and content of the gas. Generally, the definition of the gas sensor is based on the classification of the detection target, that is, the sensor for detecting the composition and concentration of the gas is called a gas sensor. Whether it is physical or chemical. For example, sensors that detect gas flow are not considered gas sensors, but thermal conductivity gas analyzers are important gas sensors, although they sometimes use a generally consistent detection principle. From its principle we can divide it into the following three categories:

1. Gas sensors using physicochemical properties: semiconductors, catalytic combustion, solid heat conduction, photoionization, etc.

2, the use of physical properties of gas sensors: such as thermal conductivity, optical interference, infrared absorption, etc.

3. Electrochemical gas sensors: current type, potential type

Catalytic combustion gas alarms, toxic gas alarms or oxygen alarms commonly used in flammable gas alarms generally use electrochemical sensors.