Assessment of Nuclear Moisture Density Gauges at a Secondary Standard Dosimetry Laboratory in Ghana during December 2015–December 2017

Document Type : Original Paper

Authors

1 Radiation Protection Institute, Ghana Atomic Energy Commission, Legon, Accra, Ghana

2 Health Physics and Instrumentation Centre, Radiation Protection Institute, Ghana Atomic Energy Commission, Accra

3 Graduate School of Nuclear and Allied Sciences, Atomic Campus, University of Ghana, Kwabenya, Accra, Ghana

Abstract

Introduction: Nuclear moisture density gauges are widely used in construction industry in different countries across the world, including Ghana, on a large scale. Like all irradiating devices, the nuclear gauges should be subjected to radiation safety assessment based on radiation protection and safety principles. Regarding this, the objective of this research was to investigate the radiation safety of the nuclear moisture density gauges to ensure the absence of any leakages from the radioactive source.
Material and Methods: For the purpose of the study, a survey meter (RADOS-120) was used to measure and record the radiation dose once at a distance of 1 m from the surfaces of all sides of the nuclear moisture density gauge and very close distance from the surfaces of the device. Moreover, the device was examined using radiation contamination test and counts on a standard block.
Results: A total of nine nuclear moisture density gauges manufactured by Troxler Electronics Inc. in the USA were evaluated within a period of 3 years. The minimum and maximum average dose rates were 0.49 and 66.67 μSv/h, respectively. The highest and lowest average dose rates were recorded in 2017 and 2016 on the devices with serial numbers of 38260 and 32839, respectively.
Conclusion: The assessment of the nuclear moisture density gauges under study revealed noradiation contamination leakage. Furthermore, all the evaluated gauges were shown to function properly and were safe for the intended purposes.

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