I. Instrument Introduction

The CIT-300FM Large-Scale Population Intra-Body Contamination Rapid Preliminary Screening System is an intelligent instrument for detecting intra-body radiation doses, developed and produced by Sichuan Xinxianda Measurement and Control Technology Co., Ltd. The instrument consists of an α and β radioactive internal contamination nasal swab detection system and a γ radioactive pulmonary internal contamination detection system. It achieves rapid measurement of the activity of radioactive substances in large populations by performing rapid energy spectrum detection of α and β through nasal swab samples and γ-ray energy spectrum detection of inhaled radioactive materials in the lungs. The instrument leads the domestic field in technologies such as multi-channel spectrometers, total measurement, data collection and processing, and method research. It is powered by a rechargeable lithium battery, is compact and lightweight, easy to carry, and utilizes a high-speed digital separation method for nuclear pulse signals, system, and digital spectrometer (Patent No.: ZL 2014 1 0000626.2), meeting high-speed data acquisition requirements. It is controlled by a single-chip microcomputer, comes with a display for online use, and features a full Chinese Windows operating system, making measurements more intuitive and operation more convenient.

The ray is converted into a pulse voltage signal by a detector, then shaped and amplified, peak detected and identified. It is then fed into a digital multi-channel analyzer, processed by a high-speed, low-power microprocessor, and displayed on an LCD screen for the user to view the spectrum and measurement results intuitively.

III. Instrument Parameters and Specifications

3.1 Measurement Indicator for Gamma Radiation:

3.1.1 Detector: Sodium Iodide Detector, Resolution: ≤7%

3.1.2 Energy range for gamma-ray measurement: 30keV-4MeV

3.1.2 Sensitivity Threshold: 150 cps/μSv/h

3.1.3 Counting Rate: ≥100 kcps

3.1.4 Stability: Instrument measurement error ≤ ±7%

3.1.5 Accuracy: The measured value of absorbed dose rate shall not exceed a limit deviation of ±10% from the calculated theoretical value.

3.2 α, β Ion Measurement Section Indicators:

3.2.1 Detector: Passivated Implanted Planar Silicon (PIPS) Detector

3.2.2 Detection Efficiency of Alpha Particles: ≥30%

3.2.3 Detection efficiency of β particles: ≥20%

3.2.4 Stability: Measurement error ≤ ±5%

3.3 Overall Instrument Parameters Index:

3.3.1 Screening Rate: ≥10 people/h

3.3.2, Main Unit Dimensions: 400×300×80mm

3.3.3, Main unit weight of the instrument: 15.0 kg.

3.3.4 Operating Environment Temperature: -10℃ to +50℃

3.3.5 Work Environment Humidity: Not exceeding 90%

3.3.6 Instrument Power Supply: DC 12V or AC 220V

3.3.7 Instrument Power: 20W

IV. Features of the Instrument:

4.1 Multiple sodium iodide detector arrays for rapid measurement of human gamma rays.

4.2 Multiple high-performance PIPS detectors can simultaneously measure α and β, or individually measure α or β.

4.3 The instrument supports ray energy spectrum display, spectrum line view zoom in/out, and the cursor moves within the channel range.

4.4 User-defined measurement time; the instrument automatically calculates the dosage result after measurement is completed.

4.5 The instrument supports large capacity data storage, and measurement parameters (including measurement time, etc.) and results (including energy spectrum, analysis results, etc.) can be saved in the internal non-volatile data storage of the instrument, facilitating paperless operation for users; 4.6 It supports functions such as automatic alarm, multi-level menu display, and the choice between automatic and manual measurement modes.

4.7 The instrument is powered by an integrated rechargeable lithium battery, which can meet extended on-site usage.

4.8 The instrument features an overall modular design, allowing for easy disassembly and convenient portability.