IEC 61563 pdf download – Radiation protection instrumentation – Equipment for measuring specific activity of gamma-emitting radionuclides in foodstuff

IEC 61563 pdf download – Radiation protection instrumentation – Equipment for measuring specific activity of gamma-emitting radionuclides in foodstuffs
1 Scope and object
1.1scope
This International Standard applies to portable instruments used for measuring the specific orvolumic activity of gamma-emitting radionuclides in food/foodstuffs intended for operationunder field conditions， particularly in case of a post-accidental situation. It does not apply tolow background laboratory instrumentation requiring highly skilled personnel.
The instruments designed for measurement of gamma contamination in foodstuffs under fieldconditions should not require special sample preparation other than machining (cutting,grinding, etc.).
These instruments may be used，in principle，to measure the gamma emitting surfacecontamination and other radiation measurements as well, but these applications are outsidethe scope of this standard.
The same instruments intended for measuring foodstuffs can also be used for themeasurement of environmental samples,such as soil，sewage,plant and animal life，etc.These instruments can be used to estimate specific gamma activity for a wide variety ofsamples according to this standard.
1.2Object
The purpose of this standard is to specify the main performance characteristics ofinstruments, intended for measurement of specific activity of gamma-emitting radionuclides infoodstuffs,their methods of testing and documentation requirements.
2Normative 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
IEC 60068-2-27:1987,Environmental testing – Part 2:Tests -Test Ea and guidance: ShockIEC 60086:(all parts) Primary batteries
3Terminology and units
The general terminology for detection and measurement of ionizing radiation and nuclearinstrumentation is given in lEC 60050(393) and lEC 60050(394).For the purpose of thisstandard the following definitions apply:
3.1
radiation meter
instrument intended to measure quantities related to ionizing radiation[IEV 394-02-01]
3.2
specific activity
activity per unit mass (Bq/kg)[IEv 393-04-13 modified]
3.3
volume activity
activity per unit volume (Bq/m3)[IEv 393-04-14 modified]
3.4
detector efficiency
ratio of the number of detected particles to the number of particles of the same type which areincident on the detector in the same time interval
[IEv 394-18-21]
3.5
response time
time required after a step variation in the measured quantity for the output signal value toreach for the first time a given percentage,usually 90 %, of its final value
[IEV 394-19-09 modified]
3.6
surface emission rate (of a source)
number of particles of a given type above a given energy emerging from the face of thesource or its window per unit time
[IEv 393-04-92]
3.7
concomitant ionizing radiation
ionizing radiation that accompanies the measured radiation but is not an object ofmeasurement and whose influence on the results should be reduced as much as possible
For gamma-radiation meters measuring under field conditions, beta-radiation is a concomitantradiation.
[IEv 393-02-22 modified]
3.8
sensitivity (of a measuring assembly)
for a given value of the measured quantity, ratio of the variation of the observed variable tothe corresponding variation of the measured quantity
[IEv 394-19-07]
3.9
effective range of measurement
range of values of the quantity to be measured over which the performance of a piece ofequipment or assembly meets the requirements of its specifications
[IEV 394-20-16]
3.10
conventionally true value of a quantity
best estimate of the value of the quantity used for a given purpose
NOTE A conventionally true value is, in general, regarded as sufficiently close to the true value for the differenceto be insignificant for the given purpose.For example, a value determined from a primary or secondary standard orby a reference instrument,may be taken as the conventionally true value,
[IEV 394-20-10]
3.11
relative intrinsic error
relative error of indication of a piece of equipment or an assembly with respect to a quantitywhen subjected to a specified reference quantity under specified reference conditions,expressed as
ei-v
where v is the indicated value of a quantity and v is the conventionally true value of thequantity at the point of measurement.
[IEV 394-20-12]
3.12
coefficient of variation
the ratio of the standard deviation s to the arithmetic mean x of a set of n measurements xgiven by the following equation: