International Electrotechnical Commission

Radiation protection instrumentation – Transportable, mobile or installed equipment to measure photon radiation for environmental monitoring - Edition 1.0
 N 61017

Annotation

This International Standard is applicable to transportable, mobile or installed assemblies intended to measure environmental air kerma rates or air absorbed dose rates from 30 nGy?h–1 to 30 ?Gy?h–1 or ambient dose equivalent rates from 30 nSv?h–1 to 30 ?Sv?h–1, or air kerma or air absorbed dose from 10 nGy to 10 mGy, or ambient dose equivalent from 10 nSv to 10 mSv, due to photon radiation of energy between 50 keV and 7 MeV. The measurable range of dose and dose rate can be extended by agreement between the purchaser and the manufacturer. This extension may be realized by combining more than one detector, for example NaI(Tl) scintillator and ionization chamber. For most environmental applications, instruments may measure over a more limited energy range of 80 keV to 3 MeV.

NOTE 1 80 keV to 3 MeV has been chosen to cover the energies of the chief environmental and man-made radionuclides that contribute to the environmental dose. The term “dose” used in this standard means the quantity, air kerma, air absorbed dose, and ambient dose equivalent, that the instrument is intended to measure.

If the assembly is to be used to measure these quantities in the area surrounding a nuclear reactor producing 6 MeV radiation from the 16N isotope, it will be necessary to determine the response at this energy. An absorbed dose in air, which uses the same unit, Gy, as air kerma can be taken to have the same numerical value as air kerma under the condition of electron equilibrium.

Passive devices such as Thermo-Luminescence Dosemeter (TLD), Optically Stimulated Luminescence (OSL) Dosemeter or Glass Radio-Photo Luminescence (RPL) Dosemeter are not covered by this standard.

Installed assemblies should be capable of operating continuously.