The BH1227 four channel low background alpha and beta measuring instrument has four independent main detectors, which can simultaneously measure four samples and provide measurements of total alpha and total beta activity concentrations in each sample. It has the characteristics of high sensitivity, simple structure, easy operation, stability and reliability. Can be equipped with any type of computer, the measurement program is localized in Chinese, the operation process has Chinese prompts, the measurement program is automatically completed and the results are printed.
This instrument is suitable for measuring total alpha and total beta in fields such as radiation protection, environmental samples, medicine and health, agricultural science, import and export commodity inspection, geological exploration, and nuclear power plants.
All performance indicators of BH1227 instrument comply with the national second level standards, which is better than similar products currently available internationally; It is the first generation product for simultaneous measurement of total alpha, total beta weak radioactivity using scintillation method both domestically and internationally; It is an ideal low background alpha beta measuring instrument in China.

Main detector

Each main detector of BH1227 instrument is composed of CR120 low-noise photomultiplier tube and ST-1221 low background alpha beta scintillator. The characteristics are:

The ST-1221 scintillator is made using a new process, which is not afraid of pollution, has a washable surface, is durable, and is inexpensive.

The counting area is large. The scintillator has a size of 21cm2 (Φ 52mm); 15.9cm2(Φ45mm)； There are three specifications of 7.1cm2 (Φ 30mm), and users can choose one according to their requirements. It can also be made according to the user's requirements.

High sensitivity. β: 0.1 × 10-2~3 × 10-2Bq; α: 5 × 10-4Bq.

Anti coincidence detector

The anti coincidence detector consists of a parallel plate with a diameter of 300 × 50mm, an ST401 plastic scintillator, and three CR119 photomultiplier tubes. Receiving a signal from any of the three tubes generated by cosmic rays will have the effect of reducing the background noise. The anti coincidence efficiency is greater than 99%.

Electronic Circuit

The electronic part of this instrument includes a low-voltage power supply, two 3kV high-voltage power supplies, and a measurement control unit.

Lead chamber

The lead chamber is made of 7.5cm lead and 1.5cm steel shell. The lead chamber is divided into upper and lower parts, with a lead thickness of 10cm. The upper lead chamber can be disassembled.
The lead chamber and electronics section are installed in a 311-625 standard cabinet.

way of working

Four detectors can simultaneously measure alpha beta radioactivity, as well as individually measure alpha or beta radioactivity. The measurement time can be arbitrarily selected.