Over deze norm
NEN-IEC 61017 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 μGy·h-1 or ambient dose equivalent rates from 30 nSv·h-1 to 30 μSv·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. 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. This standard does not provide for the measurement of beta and neutron radiation. The equipment covered by this standard comprises a detector assembly and processing circuits, which may be connected together either rigidly or by means of a flexible cable, or incorporated into a single assembly. The equipment assembly may also include circuits for displaying readings, alarms and communication. This equipment should meet the environmental conditions of use. Examples of instruments include (detailed information is described in Annex A): a) Ionization chamber This is suitable for the measurement of air kerma and air absorbed dose and dose rate. In the environment, the correction due to temperature and atmospheric pressure may be required. b) Geiger-Muller (GM) counter The energy response should be corrected. GM counters may overestimate the readings due to the dose (rate) from cosmic radiation. c) Scintillation detector The energy response should be corrected. Detailed information is described in Annex A and Annex B. d) Semiconductor detector The energy response should be corrected.
||Radiation protection instrumentation - Transportable, mobile or installed equipment to measure photon radiation for environmental monitoring