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One: Classified according to different measurement occasions

It is divided into three categories: soil radon measuring instrument, air radon measuring instrument, and water measuring radon instrument, each of which includes a variety of methods.

Two: According to the different purposes of measuring radon, the methods adopted are different

Using radon to explore uranium and thorium deposits, oil prospecting, earthquake prediction, etc., and the measurement of radon in the environment or indoors, the method used is different.

Three: Classification according to the different types of isotope

Direct measurement of radon itself or indirect measurement of the radioactivity of radon's diyi progeny radium A (RaA; it is Po) is also a classification method.

Four: Classification according to different sampling methods

You can use a pump to extract part of the atmosphere (or water and soil gas) so-called "grab samples" for determination, or you can use the passive (passive) method to wait for the radon gas to diffuse to the detector and accumulate for a period of time. analysis. The former is called warm-time (differential) measurement, and the latter is called cumulative (integral) measurement.

(1) Air radon meter

The scintillation bottle measurement method of radon concentration in the air is used in the workplace. The air radon meter can meet the environmental monitoring of uranium and radium mines, coal mines, seismic surveys, geological surveys, indoor environment, metal mines, health and environmental protection departments With scientific experiments, the radon meter is equipped with a soil sampling rod to achieve soil radon measurement (environmental monitoring users)

(2) Soil radon meter

The soil radon meter is a new type of soil "continuous", "real-time" and "automatic" radon measurement device. It uses micro-pump sampling, semiconductor detectors (silicon crystal detectors) combined with electrostatic collection of radon decay daughter RaA as the measurement object, which satisfies The sampling and measurement methods required to quantitatively measure the concentration of radon in soil and air. It has high sensitivity, easy operation, no human interference, real-time measurement and results. The measurement time can be set according to the level of radon within 1-120min. Generally, it is set to 15min. It is currently the Zgao instrument of the domestic soil radon detection automation level and is suitable for the field application of soil radon measurement in the "Code for Indoor Environmental Pollution Control of Civil Construction Engineering". For example, the JCD-260 radon measuring instrument can measure the concentration of radon in the ambient air, radon in water, and radon in the soil, as well as the radon extraction rate on the soil surface. It is portable, small in size, and light in weight. It is very suitable for field movement or fixed-point sampling. . It is widely used in radioactive prospecting and gas emission measurement and water radon concentration determination in hydration prospecting. It can also be used in the investigation and research of radon level in departments such as finding underground water sources, earthquake prediction, environmental protection, scientific research and teaching.

(3) Environmental radon meter

(4) Electronic radon meter

The electronic radon meter is not sensitive to vibration and noise, and the background reading is low. It can be used as a continuous radon detector for radon source detection. The electronic radon meter is equipped with soil and water probes to detect radon in soil and water; it is easy to operate and use, and the microcomputer indicates the operating steps. The habitual operation mode can be programmed and stored, and the radon concentration value can be recovered quickly.