IEC 62089 pdf download – Nuclear instrumentation – Calibration and usage of alpha/beta gas proportional counters
1Scope and object
This International Standard applies to alpha/beta gas proportional counting systems used forthe determination of the alpha-ray or beta-ray emission rates of radionuclides in samplecounting.The intent is to establish standard methods for calibration and use of alpha/beta gasproportional counters, including measurement of their characteristics.
Though principally applicable to beta-ray energies in excess of 100 keV,the techniquesdescribed in this standard are also useful for beta-ray energies at lower energies， provided ahigher degree of care is taken with regard to sample preparation and calibration andmeasurement details.
Normative references
The following normative documents contain provisions which，through reference in this text,constitute provisions of this International ‘Standard. For dated references，subsequentamendments to,or revisions of,any of these publications do not apply.However， parties toagreements based on this International Standard are encouraged to investigate the possibilityof applying the most recent editions of the normative documents indicated below.For undatedreferences,the latest edition of the normative document referred to applies. Members of lECand lso maintain registers of currently valid lnternational Standards.
IEC 60050(393):1996,International Electrotechnical Vocabulary (IEV) – Chapter 393:Nuclearinstrumentation: Physical phenomena and basic concepts
IEC 60050(394):1995,International Electrotechnical Vocabulary (IEV) – Chapter 394: Nuclearinstrumentation: lnstruments
IsO 8769:1988，Reference sources for the calibration of surface contamination monitors -Beta-emitters (maximum beta energy greater than 0,15 MeV) and alpha-emitters
ISO 8769-2:1996，Reference sources for the calibration of surface contamination monitors -Part 2: Electrons of energy less than 0,15 MeV and photons of energy less than 1,5 Mev
ISO:1995,Guide to the expression of uncertainty in measurement
VIlM,International vocabulary for metrology
3lnterpretations, definitions, acronyms and symbols
3.1 lnterpretations
ln this standard, the word “shall”denotes a requirement and the word “should”denotes arecommendation.The word “may” is used for stating permission but is also used in a moregeneral sense.To conform to this standard， alpha/beta gas proportional counting shall be inaccordance with its requirements but not necessarily in accordance with the recommend-ations; however, justification should be documented for deviations from a recommendation.
3.2Definitions and acronyms
For the purpose of this International Standard， the following definitions, abbreviations andacronyms apply.
3.2.1
activity (symbol: A)
quotient of dN by dr,where dN is the expectation value of the number of spontaneous nucleartransitions from a particular energy state at a given time, in the time interval dr
[IEV 393-04-10]
Symbol: A = dN/dt
3.2.2
alpha/beta emission rate
reiease of alpha/beta particles of all energies from the surface of a material into the adjoiningspace per unit time
NOTE 1 The source or sample may contain one or more alpha/beta emitting radionuclides.
NOTE 2 The surface emission rate refers to the emission from only one surface of the source or sample (alsocalled 2x emission rate); the emission rate covers the whole emission into 4T。
3.2.3
attenuation
reduction of a quantity related to radiation，such as energy，fluence,etc. upon passage ofradiation through matter,resulting from all types of interaction with matter
[lEv 393-03-20]
3.2.4
background count rate
count rate recorded by an instrument when measuring radiation from natural and man-madesources, excluding the radiation intended to be measured
Thus they are events per unit time during the measurement procedure not caused by acalibration source，but rather from that occurring in the surrounding environment or fromcosmic-ray interactions in,or adjacent to, the detector that have escaped detection by theguard detector，when present. “Contributions to the background count rate can includenaturally occurring radioactive decay in the structural materials comprising the counter,shielding, and cosmic-ray-induced ionizing radiation, as well as radon and its progeny.
3.2.5
blank count rate
count rate recorded by an instrument consisting of the background count rate with the sampleblank (planchet and sample matrix) in place
NOTE The sample blank may contain naturally occurring radionuclides and their daughter products though theseshould be limited to the minimum reasonably achievable.
3.2.6
calibration source
synonymous with radioactivity standard source (see lEv 394-20-19)
3.2.7
checking source
general term that applies to both (1) performance checking sources and (2) quality assurancechecking sources, as defined herein
IEC 62089 pdf download – Nuclear instrumentation – Calibration and usage of alpha/beta gas proportional counters
