VinaERMS-INST is a gamma dose rate monitoring system designed and manufactured by Institute for Nuclear Science and Technology (INST). It is capable of operating continuously in the field and is the main component of an environmental radiation monitoring and warning station (ERMS). The system is used for the enhancement of early warning of radioactive incidents and assist management agencies in tracing the origin as well as predicting the direction of radiation spread in the locality.
The ERMSs are typically designed with one or more radiation detectors which have high sensitivity and the ability to measure gamma dose rates over a wide range. They can be connected and transmit data wirelessly to users via the internet. The data is commonly processed and displayed on a web platform with high security. In addition, they are often installed permanently and operate without limits thanks to solar cells and backup batteries.
In Vietnam, management agencies and organizations are concerned with the needs for construction and installation of radiation monitoring stations, especially when China’s nuclear power plants are both under construction and in operation with the generatation capacity of thousands of MW near the border of our country, posing potential risks of nuclear security and radiation protection. Dealing with the situation, the Prime Minister of Vietnam approved the project “Planning the national environmental radiation monitoring and warning network until 2020” on August 31, 2010. The objectives of the project were to build a national network of environmental radiation monitoring and warning, ensure the control of environmental radiation safety, promptly detect any strange happenings related to radiation in Vietnam, support for the proactive response to nuclear and radiation incidents, and provide a national environmental radiation database for the atomic energy and nuclear safety management.
However, the number of ERMSs established has been limited and has not met the needs for monitoring and management in the country. On the basis of the funds from projects of equipment enhancement, research projects and the support from several partners such as Korea, Japan, the INST has installed and put 12 systems into operation, including 7 Fuji systems (Japan) and 5 Sara systems (Envinet, Germany) at 11 online environmental monitoring stations in Lang Son, Hai Phong, Mong Cai, Bai Chay, Lao Cai, Cao Bang, Nghe An, Son La, Da Nang, Hanoi and on Bach Long Vi island.
In order to meet the domestic demand for building a national environmental radiation monitoring network and local monitoring stations in some provinces and cities, the INST has designed and manufactured the VinaERMS-INST with the quality equivalent to foreign systems, for example, Fuji Electric, Envinet Gmbh and Enersys, etc. Besides providing accurate radiation dose values at the monitoring sites, the system must also ensure good on-site operation and comply with some international standards such as IEC-60846 and IP-67. The system shows several advantages in cost, operation, maintenance and repair.
Configuration of the VinaERMS-INST System
The VinaERMS-INST system is designed to measure the ambient dose equivalent rate H*(10) with strong points such as:
- High sensitivity combined with high accuracy over a wide measurement range;
- Compliant with the recommendations of the international standard IEC-60846 for gamma dosimeters;
Capable of good on-site performance and suitable for the climate characteristics in Vietnam.
Block diagram of the VinaERMS-INST system
The system is built as a block diagram with the main components including a combination of Geiger-Muller energy compensated tubes (GM1 and GM2) with a wide measurement range from natural background level to >1Sv/h; 32-bit microprocessor (MCU) for measuring the radioactive pulse signal from the pulse processing unit, performing the calculation algorithm to convert the counting rate to the ambient dose equivalent rate H*(10). The power supply is based on 220V AC power combined with solar cells and backup batteries (12V-30Ah) so that the system can operate continuously outdoors. The data is measured in real time, stored in the SD card and displayed on the LED or liquid crystal display (Display-LED/GLCD). The system uses IoT technology for the data transmission to the operating center on a cloud server via GSM, wifi/4G/3G/GPRS network. Users can access and control the system via the web platform from any smart device such as a computer, a tablet, or a mobile phone with internet connection. In addition, the system also has the option of adding temperature, humidity, and precipitation sensors (Temp. and Humi. Sensors) to get more information for users in considering the dependence of the recorded dose rate correlated with the weather data at the measured area. All radiation detectors and functional electronic units are placed in an IP-66 protected enclosure.
|Detector type||Geiger-Muller energy compensated tubes, Qty: 02|
|Radiations||Photon (Gamma, X-ray)|
|Quantity||H*(10) (Ambient equivalent dose rate)|
|Energy range||38 keV to 1.3 MeV (±25 %)
35 keV to 2.5 MeV (-29% to +67 %)
|Dose rate range||100 nSv/h – 1Sv/h|
|Accuracy||± 15% (calibrated to Cs-137)|
|Angular dependence of the response||± 20% ( -90o to 90o, 137Cs)|
|Interface||Serial communication (RS232), Wifi/4G/3G/GPRS|
|Display||Led panel/GLCD (optional)|
|Power supply||AC 220V 50/60 Hz, 12V 30Ah backup batteries, Solar cells|
|Operating temperature and humidity range||-10oC to 70oC, 100% RH|
|Complying with the international standards||IEC 60846, IP 66|
|Alarm thresholds||2 alarm threshold setting|
|Weight||< 25 kg|
|Measurement||– Ambient Dose Equivalent Rate H*(10) and real-time data storage.|
|Data communication||– Communication with a computer through a USB port (type-B) via RS232 protocol.
– Data transfer to users via: Wifi/4G/3G/GPRS. Collected data is displayed on a web platform, accessible to all wireless devices that use the internet.
– Sending SMS messages, retrieving information about Location, Dosage, System Status in real time.
|Storage||– Data is stored in a 128Gb memory card (SD card) according to the structure: time, dose rate, system status.|
|System status and fault diagnosis||– Notification and diagnosis of system status when an error occurs (power, high voltage, data transmission recording system, …)
– Selection of humidity and temperature sensors to observe environmental fluctuations where the system operates.
Mechanical structure of the VinaERMS-INST system
Nguyen Duc Tuan
Institute for Nuclear Science and Technology
179 Hoang Quoc Viet Str., Cau Giay Dist., Hanoi, Vietnam
Mobile: +84 913698860
Email address: firstname.lastname@example.org