IEC 60522:1999 pdf download – Determination of the permanent filtration of X-ray tube assemblies

IEC 60522:1999 pdf download – Determination of the permanent filtration of X-ray tube assemblies.
1.2 Object
IEC 60522 defines the concept of PERMANENT FILTRATION in X•RAY TUBE ASSEMBLIES tot medical diagnosis and RADIOTHERAPY and describes a method for its determination. It contains requirements for statements of compliance for ACCOMPANYING DOCUMENTS and for markings on X-RAY TUBE ASSEMBLIES.
Methods are given to determine the PERMANENT FILTRATION in an X-RAY TUBE ASSEMBLY with an accuracy that is sufficient to enable the appropriate ADDITIONAL FILTRATION to be provided in order to attain the desired TOTAL FILTRATION.
NOTE I Thit standard does not contain requirements for any specific values of PERMANENT FILTRATION 01 TOTAl. FILTRA11ON to be pro.aed. For X.RAY rJaE ASSSUBLIE5 and X-RAY EQUIPMENT used for d.agnostvc pw’poses, appropriate requlr.nl.nts rc 9Iven in IEC 60601-1.3,
NOTE 2 The method of delemunatlon described In this standard is suitable as a type test, It Is not Intended as a test to be applied by the USER
2 Normative references
The following referenced documents are indispensable tot the application of this document. For dated references, only the edition cited applies. Fur undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60601-1:1988, Medical electrical equipment — Part 1: General requirements foe’ safety
Amendment No, 1(1991)
Amendment No. 2 (1995)
IEC 60601-1-3:1994. Medical electrical equipment — Part 1: General requirements for safety — 3. Collateral Standard: General requirements for radiation protection in diagnostic X-ray equipment
IEC 60788:1984, Medical radiology – Terminology
ISO 2092:1981, Light metals and their alloys — Code of designation based on chemical symbols
4.1 General
The PERMANENT FILTRATION IS determined by measuring the QUALITY EQUIVALENT FILTRATION of
samples of the permanently fixed materials, used In the construction of the X-RAY TUBE ASSEMBLY, that intercept the X-RAY BEAM. Where appropriate, a composite sample replicating the combination of the various materials and their thicknesses, as actually used in the
construction, can be tested. Alternatively, the PERMANENT FILTRATION can be computed from measurements on samples of the individual materials concerned, provided that:
— the reference material is the same for each sample and,
– the RADIATION QUALITY of the X-RAY BEAM used for the determination is adjusted to compensate for the absence of any components of the PERMANENT FILTRATION missing from the sample and normally located between the sample and the FOCAL SPOT
NOTE The result 04 the determination Is vahd only tot a partlculat combnalioe of matenels. as testea, In manufacture, the composition and thicknesses 01 malenais actually used must be controlled eIhtn ap(wopnats limits. in order to rnaaritain compliance wlh any stated yalu. of PERMANtNT FIL1ATON
4.2 T.st sample
Use a test sample, replicating, in accordance with 4.1, either the complete composition 01 layers of different materials, or a layer of an individual material, as used in the construction of the X-RAY TUBE ASSEMBLY concerned to effect the whole or part of its PERMANENT FILTRATION.
4.3 GeneratIon of the X-RAY BEAM for measurement
To generate the X-RAY BEAM for measurement, use an X-RAY TUBE with a target of the same material as the X-RAY TUBE ASSEMBLY under test at an X-RAY TUBE VOLTAGE with a PERCENTAGE RIPPLE not exceedIng 10 and a value chosen as follows:
a) for X-RAY TUBE ASSEMBLIES in which the PERMANENT FILTRATION contains a material with a K-edge absorption energy at 19 keV or above, use an X-RAY TUBE VOLTAGE corresponding to the K-edge energy of the material, for example 20 kV for molybdenum with a K-edge at 19,99 key: otherwise
b) for X-RAY TUBE ASSEMBLIES designed for a narrow range of X-RAY TUBE VOLTAGE (e.g. CT-application), the NOMINAL X-RAY TUBE VOL TAGE; of
C) for X-RAY TUBE ASSEMBLIES with a NOMINAL X-RAY TUBE VOLTAGE not exceeding 65 kV, the NOMINAL X-RAY TUBE VOL TAGE of
d) for X-RAY TUBE ASSEMBLIES with a NOMINAL X-RAY TUBE VOLTAGE exceeding 65 kV, 75 kV or approximately half the NOMINAL X-RAY TUBE VOLTAGE, whichever is the greater. It is desirable to avoid testing close to the absorption edge of tungsten.
For testing with a composite sample, use an X-RAY BEAM with negligible TOTAL FILTRATION (e.g.
a ber1lium window), For testing with a sample of a single material, add an appropriate
thickness of the reference material between the material under test and the FOCAL SPOT. This Is
to compensate for the effect on the RADIATION QUALITY at the ENTRANCE SURFACE of the sample
01 omitting any layers of material foiming part of the actual PERMANENT FILTRATION.