Process radiation monitoring is the key component of radiation monitoring system at any nuclear facility, including NPPs. The radiation monitoring of nuclear process systems can be ensured by obtaining complete information from spectrometric measuring instruments whose detection sensitivity and selectivity allow for the monitored fluids to meet the specified requirements. The spectrometric method for detection of target radionuclides in the monitored fluid is more informative when compared to measuring of radionuclide total activity, which is done on the basis of an integral dependence of detector response on ionizing radiation impact.
The spectrometric method provides high quality and reliability of measurements needed both for early discrepancy detection and for proper assessment of population and environment radiation exposure. A set of automated radiometers-spectrometers is an innovative product that is used for spectrometric radiation monitoring of a wide range of objects and can be integrated into automated radiation monitoring systems.
A set of radiometers-spectrometers is a new-generation instrument having no rival outside of Russia and used for obtaining the data needed to monitor the integrity of protective barriers of nuclear power installations both under normal and abnormal operating conditions. A set of radiometers-spectrometers has been developed in accordance with the requirements of the RF regulatory documents.
The radiometers-spectrometers are designed to operate both autonomously and as an integrated component of automated radiation monitoring systems at NPPs and other nuclear facilities. Radiometers-spectrometers operate on a long-term basis.
| Technical characteristics | |
| Energy range of measured gamma-radiation, MeV | 0.05 to 3 |
| Max integral nonlinearity of a spectrometric route | 1% |
| Max input statistical loading of a spectrometric route, counts per second | 100000 |
| Admissible relative error for volumetric activity measurements,% | ±50 |
| Instability spectrometric route conversion for 24-hour continuous operation, not more than, % | 2 |
| Max warm-up time, min | 30 |
| Voltage of AC power supply mains with frequency of 48 to 51 Hz, V | 176 to 253 |
| Max power consumption, VA | 100 |
The following measuring instruments are designed for series production:
- MGG-010 radiometer-spectrometer for monitoring of inert gas volumetric activity
- MGG-021 radiometer-spectrometer for monitoring of iodine volumetric activity
- MAG-030 radiometer-spectrometer for monitoring of aerosol volumetric activity
- MAG-031 radiometer-spectrometer for monitoring of aerosol volumetric activity
- MZHG-040 radiometer-spectrometer for monitoring of liquids volumetric activity
- MIG-050 radiometer-spectrometer for monitoring of source volumetric activity
- MZHG-080 radiometer-spectrometer for monitoring of liquid effluent volumetric activity
The advantages of radiometer-spectrometers are as follows:
- long-term operation under severe operating conditions at industrial facilities;
- hardware commonality, which reduces a spare parts inventory, personnel training costs, and makes maintenance easier;
- use of advanced solutions (digital processing of signals, use of new detectors with LaBr3(Ce) crystals and analytical filters with high-selective sorbents, special operation algorithms etc.) to ensure high informativeness and reliability of monitoring;
- achievement if reasonable energy resolution (no more than 3.5% for Cs-137) without using sophisticated and expensive cryogenic systems for detectors cooling;
- full spectrometric measurements and reception of pulse-height distribution for the whole energy spectrum;
- building of a mathematical model and processing of each gamma-ray spectrum, including identification of isotopic composition and contribution of individual radionuclides to the spectrum;
- calculation of volumetric activity of all detected radionuclides;
- calculation of volumetric activity measurement uncertainty at Р=0.95 and evaluation of minimal measured activity for specified radionuclides;
- advanced automated operation and data processing algorithms;
- saving of data processing results and diagnostics information in local database of a radiometer-spectrometer.
Methodologically, the radiometers-spectrometers are mainly intended to monitor the parameters of reference radionuclides with high radioactivity that is convenient for measurements. Radiometers-spectrometers are developed on the basis of methods protected by the inventor’s certificates, tested and entered into the RF Register of Measuring Equipment.