1、 _ _ CENELEC EN*bL262-2 74 3404583 OlYOL3 TOO BRITISH STANDARD Characteristics of electro-optical X-ray image intensifiers for medical electrical equipment Part 2. Determination of the conversion factor The European Standard EN 61262-2 : 1994 has the status of a British Standard BS EN 61262-2 : 1995
2、 JEC 1262-2 : 1994 BS EN 61262-2 : 1995 Date This British Standard, having been prepared under the direction of the Health and Environment Sector Board (H-), was published under the authority of the Standards Board and comes into effect on 15 March 1995 O BSI 1995 Rxt affected The following BSI refe
3、rences relate to the work on this standard: Committee reference HCC/72 Draft for comment 94/501342 DC ISBN O 580 23691 2 Committees responsible for this British Standard The preparation of this British Standard was entrusted to %chnical Committee HCC/72, Image intensifiers, upon which the following
4、bodies were represented: Association of X-ray Equipment Manufacturers (BEAMA Ltd .) British Institute of Radiology College of Radiographers Institute of Physical Sciences in Medicine (Ipsm) Amendments issued since publication Amd. No. CENELEC EN*b1262-2 94 m 3404583 0149015 883 m BS EN 61262-2 : 199
5、5 Contents Committees responsible Inside front cover National foreword ii Foreword 2 Bxt Of EN 61262-2 4 i CENELEC EN*b1262-2 94 = 3404583 0149016 71T W BS EN 61262-2 : 1995 National foreword This British Standard has been prepared by Technical Committee HCC/72 and is the English language version of
6、 EN 61262-2 : 1994 Medical electrical equipment - Charactemstics of electro-optical X-ray image intens - Part 2 Determination of the conversion factor, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 1262-2 : 1994 published by the Internat
7、ional Electrotechnical Commission (IEC). It supersedes BS 6252: 1982, which is withdrawn. Cross-references Publication referred to HD 501 S1 (IEC 788 : 1984) Additional information. The following print types are used in this standard. Requirements, with which compliance can be tested, and definition
8、s: Corresponding British Standard BS 6641 : 1985 Glossary of medical radiology terms in roman type. Explanations, advice, general statements, exceptions and references: in smaier type. %st procedures: in italic type Terms defined in clause 3 of this standard and in annex A: in SMALL c PITA IS. For t
9、he purposes of this British Standard, any references to IEC page numbers in the text should be ignored. Compliance with a British Standard does not of itself confer immunity from legal obiigations. I ii CENELEC EN*bL2b2-2 94 D 3404583 OL4OL7 656 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 6
10、1262-2 September 1994 ICs 11.040.50 Descriptors: Medical electrical equipment, image intensifier, X-ray, conversion factor Supersedes HD 512 S1 : 1989 English version Medical electrical equipment - Characteristics of electro-optical X-ray image intensifiers Part 2: Determination of the conversion fa
11、ctor (IEC 1262-2 : 1994) Appareils lectromdicaux - Caractristiques des intensificateurs lectro-optiques dimage radiologique Rntgenbildverstrkern Partie 2: Dtermination du facteur de Medizinische elektrische Gerte - Merkmale von elektronenoptischen Teil 2: Bestimmung des Konversionsfaktors conversion
12、 (IEC 1262-2 : 1994) (CE1 1262-2 : 1994) This European Standard was approved by CENELEC on 1994-07-05. CENELEC members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteratio
13、n. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by transl
14、ation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland) Ireland
15、, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 36,
16、 B-1050 Brussels O 1994 Copyright reserved to CENELEC members Ref. No. EN 61262-2 : 1994 E CENELEC EN*b12b2-2 94 3404583 Oh490h8 592 Page 2 EN 61262-2 : 1994 Foreword The text of document 62B(C0)113, as prepared by Sub-committee 62B: Diagnostic imaging equipment, of IEC %chnical Committee 62: Electr
17、ical equipment in medical practice, was submitted to the IEC-CENELEC parallel vote in January 1994. The reference document was approved by CENELEC as EN 61262-2 on 5 July 1994. This European Standard replaces HD 512 SI : 1989. The following dates were fixed: - latest date of publication of an identi
18、cal national standard (dp) 1995-07-01 - latest date of withdrawal of conflicting national standards (dow) 1995-07-01 For products which have complied with HD 512 S1 : 1989 before 1995-07-01, as shown by the manufacturer or by a certification body, this previous standard may continue to apply for pro
19、duction until 2000-07-01. Annexes designated normative are part of the body of the standard. Annexes designated informative are given only for information. In this standard, annexes A and B are informative and annex ZA is normative. CENELEC EN*bL262-2 94 9 3404583 OL49OLi 429 9 Page 3 EN 61262-2 : 1
20、994 CONTENTS Page 2 FOREWORD Clause 1 Scope . 4 2 Normative reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 Terminology . 4 3.1 3.2 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、. . . . . . . . . . Degree of requirements and reading instructions 4 5 . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Requirements 6 6 6 6 7 7 4.1 Test Set-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Input radiation . . . .
22、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 TESTDEVICE 4.5 Measurement equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 X-RAY IMAGE INTENSIFIER - Operating conditions . . . . . . . . . . . . . .
23、 . . . . . . . . . . . . . 5 Determination Of the CONVERSION FACTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5.1 Preparation . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5.2 Measurement . . . . . . . . .
24、. . . . . . . . . . . . . . . . . . . . . . . . . : . . . . . . . . . . . . . . . . 7 5.3 Corrections . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.4 Determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、. . . . . . . . . . . . . . . 8 6 PreSentatiOn Of the CONVERSION FACTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 7 Statement of compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . 9 Annexes A Terminology - Inde
26、x of terms . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 B Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 ZA Other international publications quoted in this standard with the
27、 references of the relevant European publications . 12 CENELEC ENabL2b2-2 74 = 3404583 0349020 140 = Page 4 EN 61262-2 : 1994 MEDICAL ELECTRICAL EQUIPMENT - CHARACTERISTICS OF ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIERS - Part 2: Determination of the conversion factor 1 Scope This International Standar
28、d appiieS tO ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIERS for medical Use, as COfnpOnentS Of diagnostic X-RAY EQUIPMENT. This International Standard describes a method of determining the CONVERSION FACTOR of X-RAY IMAGE INTENSIFIERS. It is applicable only to devices whose output light spectra do not sig
29、nificantly deviate from that of a P-20 phosphor. 2 Normative reference The following standard contains provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the edition indicated was valid. All standards are subject to rev
30、ision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IEC 788: 1984, Medical Radiol
31、ogy - Terminology 3 Terminology 3.1 Definitions For the purposes of this International Standard, the following definitions apply together with those given in IEC 788. The definitions given below take preference over those given in IEC 788 when differences occur. 3.1.1 XRII: An abbreviation for ELECT
32、RO-OPTICAL X-RAY IMAGE INTENSIFIER. 3.1.2 ENTRANCE PUNE: The plane perpendicular to the axis of symmetry of the XRII and grazing the part of the XRII, including its housing, that protrudes most in the direction of the RADIATION SOURCE. 3.1.3 NTRANCE FIELD: For an XRII, the area in the ENTRANCE PLANE
33、 that can be used for the transmission of an X-RAY PATTERN under specific conditions. 3.1.4 ENTRANCE FIELD SIZE: For an XRII, the diameter of the field in the ECE PLANE that can be used at a specified SED for the transmission of an X-RAY PATTERN. For an XRII with more than one magnification mode, th
34、e ENTRANCE FIELD SIZE for each of the magnification modes shall correspond to the same diameter of the XRII OUTPUT IMAGE occuring with the largest ENTRANCE FIELD SIZE. CENELEC EN*bL2b2-2 94 3404583 OL4902L 087 Page 6 EN 61262-2 : 1994 3.1.5 SOURCE TO ENTRANCE PLANE DISTANCE (abbreviation: SED): The
35、distance between the -Ai SPOT Of the X-RAY TUBE and the ENTRANCE PLANE Of the XRII. 3.1.6 CENTRE OF THE OUTPUT IMAGE: The Centre Of the smallest Circle circumscribing the OUTPUT IMAGE. 3.1.7 CENTRE OF THE ENTRANCE HELD: That POint in the ENTRANCE PLANE which iS imaged at the CENTRE OF THE OUTPUT IMA
36、GE. 3.1.8 CENTRAL AXIS: The line perpendicular to the ENTRANCE PLANE passing through the CENTRE OF THE ENTRANCE FIELD. 3.1.9 Not used 3.1 .1 0 CONVERSION FACTOR: The ratio Of the lUmnanCe in the CENTRE OF THE OUTPUT IMAGE Of a Specific zone in the OUTPUT IMAGE to the AIR KERMA RATE in the CENTRE OF
37、THE EMFiANCE FIELD. 3.2 Degree of requirements and reading instructions in this International Standard the auxiliary verb: - “shall“ - “Should“ - “may“ implies that compliance with a requirement is mandatory for compliance with the standard; implies that compliance with a requirement is strongly rec
38、ommended but is not mandatory for compliance with the standard; implies that compliance with a requirement is permlted to be accomplished in a particular manner, for compliance with the standard; and the following words have the meaning: - “specific“ when used in combination with parameters or condi
39、tions: refers to a particular value or standardized arrangement, usually to those required in an IEC standard or a legal requirement; see IEC 788, rm-74-01. - “specified“ - “designed for“ when used in combination with parameters or conditions: refers to a value or arrangement to be chosen for the pu
40、rpose under consideration and indicated usually in the ACCOMPANYING DOCUMENTS; see IEC 788, rm-7442. when used in standards to characterize equipment, devices, components or arrangements: designates an intended and usually apparent purpose or use for the product. CENELEC EN*b1262-2 94 = 3404583 0349
41、022 TL3 bge 6 EN 61262-2 : 1994 4 Requirements 4.1 Test set-up a) The SED shall be 100 cm i 1 cm. b) The FOCAL SPOT of the X-RAY TUBE shall be on the CENTRAL Axis. C) The distance between the FOCAL SPOT Of the X-RAY TUBE and any ADDED FILTERS shall not exceed 33 cm. d) The X-RAY FIELD shall cover th
42、e ENTRANCE FIELD entirely, but its area shall not exceed the ENTRANCE FIELD area by more than 10 %. This limitation of the X-RAY FIELD shall be made by a DIAPHRAGM placed immediately in front of the ENTRANCE PLANE. The BEAM LIMITING DEVICE Of the X-RAY SOURCE ASSEMBLY shall be Used to limit the X-RA
43、Y BEAM on this DIAPHRAGM. The DIAPHRAGM shall provide an ATTENUATION RATIO Of at least 100 for the quantity AIR KERMA RATE. e) The CONVERSION FACTOR varies with temperature and the measurements shall refer to normal room temperatures (.e. 23 OC i 3 OC). 4.2 X-RAY IMAGE IN7ENSlFm? - Operating conditi
44、ons a) The XRII shall be operated under the conditions for NORMAL USE as specified by the manufacturer. b) NO ANTI-SCAlTER GRID Of protective cover shall be USd. c) In the case of multiple-field XRIIs, the measurement shall be made for the largest specified ENTRANCE FIELD. Measurements for other ENT
45、RANCE FIELDS are optional. 4.3 input radiation a) The TOTAL FILTRATION of the incident X-RAY BEAM shall be 223 mm f 0,5 mm of aluminium equivalent of which at least 20 mm is aluminium (99,9 % purity). The HALF-VALUE LAYER at the position corresponding to the CENTRE OF THE ENTRANCE FIELD shall be 7.0
46、 mm Al f 0,2 mm Al (99,9 % purity). This condition corresponds to an approximate X-RAY TUBE VOLTAGE Of 75 kV. b) The AIR KERMA RATE in the ENTRANCE PLANE shall be such that linear operation Of the XRII and the detectors employed in the measurement is ensured. An AIR KERMA RATE of 1 pGy s- to 100 pGy
47、 s- is recommended. c) The temporal fluctuations of the AIR KERMA RATE shall not impair the measurement accuracy by more than 2 %. As the AIR KERMA RATE measurements and the luminance measurements are .made at different time instances, the X-RAY TUBE output shall be monitored and the results of the
48、measurements shall be corrected to meet this requirement. d) The AIR KERMA RATE at any location in the ENTRANCE FIELD shall not be leSS than 70 % Of the highest value Of the AIR KERMA RATE in the ENTRANCE FIELD. CENELEC ENxb12b2-2 q4 3404583 0199023 95T = Page 7 EN 61262-2 : 1994 4.4 TEST DEVICE Not
49、 used. 4.5 Measurement equipment 4.5.1 Device for measuring the AIR KERMA RATE The device shall be accurate to within 15 %. 4.5.2 Device for measuring the luminance of the OUTPUT SCREEN a) The device shall measure the luminance in the direction perpendicular to the plane defined by the OUTPUT SCREEN. If the angular distribution of the luminance deviates by more than 25 Yo from Lamberts law within a range of O O up to 30 O with respect to the perpendicular of the OUTPUT IMAGE, the measurement should be carried out with an acceptance angle 5 O maxim
