1、BRITISH STANDARD BS EN 61262-1:1995 IEC1262-1: 1994 Characteristics of electro-optical X-ray image intensifiers for medical electrical equipment Part1: Determination of the entrance field size The European Standard EN61262-1:1994 has the status of a BritishStandardBSEN61262-1:1995 This BritishStanda
2、rd, having been prepared under the directionof the Health and Environment Sector Board (H/-), was published under the authorityof the Standards Boardand comes into effect on 15April1995 BSI 01-2000 The following BSI references relate to the work on this standard: Committee reference HCC/72 Draft for
3、 comment94/501341 DC ISBN 0 580 23590 4 Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted to Technical Committee HCC/72, Image intensifiers, upon which the following bodies were represented: Association of X-ray Equipment Manufacturers (BEAMA Ltd.)
4、 British Institute of Radiology College of Radiographers Institute of Physical Sciences in Medicine (Ipsm) Amendments issued since publication Amd. No. Date CommentsBSEN61262-1:1995 BSI 01-2000 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN61262-
5、1 3 List of references Inside back coverBSEN61262-1:1995 ii BSI 01-2000 National foreword This BritishStandard has been prepared by Technical Committee HCC/72 and is the English language version of EN61262-1:1994 Medical electrical equipment Characteristics of electro-optical X-ray image intensifier
6、s Part1Determination of the entrance field size, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC1262-1:1994 published by the International Electrotechnical Commission (IEC). It supersedes BS6893:1988, which is withdrawn. Additional informa
7、tion. The following print types are used in this standard. Requirements, with which compliance can be tested, and definitions: inromantype. Explanations, advice, general statements, exceptions and references: insmaller type. Test procedures: in italic type. Terms defined in clause3 of this standard
8、and in Annex A: in SMALL CAPITALS. For the purposes of this BritishStandard, any references to IEC page numbers in the text should be ignored. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct appli
9、cation. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding BritishStandard HD501 S1 (IEC788:1984) BS6641:1985 Glossary of medical radiology terms Summary of pages This document comprises a front cover,
10、an inside front cover, pagesi andii, theEN title page, pages2 to8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EURO
11、PENNE EUROPISCHE NORM EN61262-1 September 1994 ICS 11.040.50 Supersedes HD510 S1:1988 Descriptors: Medical electrical equipment, image intensifier, X-ray, entrance field Englishversion Medical electrical equipment Characteristics of electro-optical X-ray image intensifiers Part1:Determination of the
12、 entrance field size (IEC1262-1:1994) Appareils lectromdicaux Caractristiques des intensificateurs lectro-optiques dimage radiologique Partie1: Dtermination de la dimension du champ dentre (CEI1262-1:1994) Medizinische elektrische Gerte Merkmale von elektronenoptischen Rntgenbildverstrkern Teil1: Be
13、stimmung der Eingangsfeldgre (IEC1262-1:1994) This European Standard was approved by CENELEC on 1994-07-05. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alt
14、eration. 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
15、translation 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, I
16、reland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassar
17、t 35, B-1050 Brussels 1994 Copyright reserved to CENELEC members Ref. No. EN61262-1:1994 EEN61262-1:1994 BSI 01-2000 2 Foreword The text of document62B(CO)112, as prepared by Sub-Committee62B: Diagnostic imaging equipment, of IEC Technical Committee62: Electrical equipment in medical practice, was s
18、ubmitted to the IEC-CENELEC parallel vote in January1994. The reference document was approved by CENELEC as EN61262-1 on 5July1994. This European Standard replaces HD510 S1:1988 The following dates were fixed: For products which have complied with HD510S1:1988 before1995-07-01, as shown by themanufa
19、cturer or by a certification body, this previous standard may continue to apply for production until2000-07-01. Annexes designated “normative” are part of the body of the standard. Annexes designated “informative” are given only for information. In this standard, Annex A and Annex B are informative
20、and Annex ZA is normative. Contents Page Foreword 2 Introduction 3 1 Scope 3 2 Normative reference 3 3 Terminology 3 3.1 Definitions 3 3.2 Degree of requirements and reading instructions 4 4 Requirements 4 4.1 Test set-up 4 4.2 X-RAY IMAGE INTENSIFIER Operating conditions 4 4.3 Input radiation 4 4.4
21、 TEST DEVICE 4 4.5 Measurement equipment 4 5 Determination of the USEFUL ENTRANCE FIELD SIZE and NOMINAL ENTRANCE FIELD SIZE 4 5.1 Preparation 4 5.2 Measurement 5 5.3 Corrections 5 5.4 Determination 5 6 Presentation of the ENTRANCE FIELD SIZE 5 7 Statement of compliance 5 Annex A (informative) Termi
22、nology Index of terms 6 Annex B (informative) Derivation of the NOMINAL ENTRANCE FIELD SIZE 7 Annex ZA (normative) Other international publications quoted in this standard with the references of the relevant European publications 8 Figure B.1 Geometry of test set-up 7 latest date of publication ofan
23、 identical national standard (dop) 1995-07-01 latest date of withdrawal ofconflicting national standards (dow) 1995-07-01EN61262-1:1994 BSI 01-2000 3 Introduction The ENTRANCE FIELD SIZE of the ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIER can be specified in several ways depending on the specific SED. Ty
24、pically, the ENTRANCE FIELD SIZE is specified as a NOMINAL ENTRANCE FIELD SIZE or as a USEFUL ENTRANCE FIELD SIZE. The SOURCE TO ENTRANCE PLANE DISTANCE (SED) for the NOMINAL ENTRANCE FIELD SIZE is infinite, while the USEFUL ENTRANCE FIELD SIZE is measured at a specific SED, usually one meter. Both
25、the NOMINAL ENTRANCE FIELD SIZE and the USEFUL ENTRANCE FIELD SIZE are considered in this standard. The NOMINAL ENTRANCE FIELD SIZE is calculated from several USEFUL ENTRANCE FIELD SIZE measurements. Measurements of the USEFUL ENTRANCE FIELD SIZE in the magnification modes of the ELECTRO-OPTICAL X-R
26、AY IMAGE INTENSIFIER will also be considered. 1 Scope This International Standard applies to ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIERS for medical use, as components of diagnostic X-RAY EQUIPMENT. This International Standard describes a method of determining the ENTRANCE FIELD SIZE of X-RAY IMAGE INT
27、ENSIFIERS. 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 revision, and parties to agreements based
28、 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 ISO maintain registers of currently valid International Standards. IEC788:1984, Medical Radiology Terminology. 3 Terminology 3.1 Defin
29、itions 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 IEC788 when differences occur. 3.1.1 XRII an abbreviation for ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIER 3.1.2 EN
30、TRANCE PLANE 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 ENTRANCE FIELD for an XRII, the area in the ENTRANCE PLANE that can be used for the transmission of an
31、X-RAY PATTERN under specific conditions 3.1.4 ENTRANCE FIELD SIZE for an XRII, the diameter of the field in the ENTRANCE 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, the ENTRANCE FIELD SIZE for each of the magn
32、ification modes shall correspond to the same diameter of the XRII OUTPUT IMAGE occurring with the largest ENTRANCE FIELD SIZE 3.1.5 SOURCE TO ENTRANCE PLANE DISTANCE (abbreviation SED) the distance between the FOCAL SPOT of the X-RAY TUBE and the ENTRANCE PLANE of the XRII 3.1.6 CENTRE OF THE OUTPUT
33、 IMAGE the centre of the smallest circle circumscribing the OUTPUT IMAGE 3.1.7 CENTRE OF THE ENTRANCE FIELD that point in the ENTRANCE PLANE which is imaged at the CENTRE OF THE OUTPUT IMAGE 3.1.8 CENTRAL AXIS the line perpendicular to the ENTRANCE PLANE passing through the CENTRE OF THE ENTRANCE FI
34、ELD 3.1.9 Not used 3.1.10 NOMINAL ENTRANCE FIELD SIZE the ENTRANCE FIELD SIZE of the XRII that would be achieved with a parallel beam of IONIZING RADIATION with the RADIATION SOURCE approaching infinity 3.1.11 USEFUL ENTRANCE FIELD SIZE the ENTRANCE FIELD SIZE measured at the ENTRANCE PLANE of the X
35、RII at a specified SEDEN61262-1:1994 4 BSI 01-2000 3.2 Degree of requirements and reading instructions In this International Standard the auxiliary verb: and the following words have the meaning: 4 Requirements The instrumentation characteristics and the settings needed for the determination of the
36、ENTRANCE FIELD SIZE are given here. 4.1 Test set-up a) The SED shall be100cm 1cm. To determine the NOMINAL ENTRANCE FIELD SIZE, an additional measurement is required at an SED that is different from100cm. For this measurement, an SED of about50cm is recommended. b) The FOCAL SPOT of the X-RAY TUBE s
37、hall be on the CENTRAL AXIS. c) The X-RAY FIELD shall cover the ENTRANCE FIELD entirely. 4.2 X-RAY IMAGE INTENSIFIER Operating conditions a) The XRII shall be operated under the conditions for NORMAL USE as specified by the manufacturer. b) Not used. c) In the case of multiple-field XRIIs, the measu
38、rement shall be made for the largest specified ENTRANCE FIELD. Measurements for other ENTRANCE FIELDS are optional. 4.3 Input radiation The combination of the ATTENUATION EQUIVALENT of the TEST DEVICE and the RADIATION QUALITY used for the determination of the values of magnification shall be such t
39、hat the image of the TEST DEVICE has a high contrast. The radiation intensity shall be sufficient to obtain an image at a low noise level. 4.4 TEST DEVICE a) The TEST DEVICE shall be a radio-opaque scale sufficient in size to cover the normal mode of the XRII. The smallest division of the scale shal
40、l not be larger than2,0mm. b) The TEST DEVICE shall have two orthogonal scales to facilitate centering of the device in the ENTRANCE FIELD. c) The TEST DEVICE shall be placed tangent to the ENTRANCE PLANE. 4.5 Measurement equipment A telescope or microscope is recommended to view the OUTPUT IMAGE fo
41、r alignment of the TEST DEVICE in the ENTRANCE FIELD. The telescope or microscope is also suggested for the determination of the actual measurement of the ENTRANCE FIELD SIZE. 5 Determination of the USEFUL ENTRANCE FIELD SIZE and NOMINAL ENTRANCE FIELD SIZE 5.1 Preparation a) The TEST DEVICE shall b
42、e placed in a plane as close as possible to, but not more than10mm in front of, and parallel to the ENTRANCE PLANE. b) The centre of the TEST DEVICE shall be on the CENTRAL AXIS. c) For measuring the USEFUL ENTRANCE FIELD SIZE the SED shall be adjusted to100cm 1cm, see4.1 a). “shall” implies that co
43、mpliance with a requirement is mandatory for compliance with the standard; “should” implies that compliance with a requirement is strongly recommended but is not mandatory for compliance with the standard; “may” implies that compliance with a requirement is permitted to be accomplished in a particul
44、ar manner, for compliance with the standard; “specific” when used in combination with parameters or conditions: refers to a particular value or standardized arrangement, usually to those required in an IEC standard or a legal requirement; seeIEC788, rm-74-01. “specified” when used in combination wit
45、h parameters or conditions: refers to a value or arrangement to be chosen for the purpose under consideration and indicated usually in ACCOMPANYING DOCUMENTS; seeIEC788, rm-74-02. “designed for” when used in standards to characterize equipment, devices, components or arrangements: designates an inte
46、nded and usually apparent purpose or use for the product.EN61262-1:1994 BSI 01-2000 5 5.2 Measurement a) While the XRII is irradiated, determine the maximum dimension of the TEST DEVICE as seen in the OUTPUT IMAGE with the SED at100cm1cm. The use of a telescope or microscope to view the OUTPUT IMAGE
47、 is suggested to improve accuracy. In order to measure the USEFUL ENTRANCE FIELD SIZE in the magnification modes, it is necessary to make a relative or absolute measurement of the OUTPUT IMAGE diameter in the normal or non-magnification mode. The USEFUL ENTRANCE FIELD SIZE for each of the magnificat
48、ion modes shall correspond to the same diameter of the XRII OUTPUT IMAGE, as the one occurring in the normal mode of the XRII. b) Repeat the measurement as described in5.2 a) with an SED of about50cm for the determination of the NOMINAL ENTRANCE FIELD SIZE. 5.3 Corrections Not used. 5.4 Determinatio
49、n The USEFUL ENTRANCE FIELD SIZE is a direct measurement requiring no calculations or corrections. However, to determine the NOMINAL ENTRANCE FIELD SIZE a calculation based on data taken at two different SEDs is needed. The NOMINAL ENTRANCE FIELD SIZE is calculated as follows: d 3 =d 1 d 2 (A B)/(A d 1 )(B d 2 ) where SeeAnnex B and Figure B.1 for derivation of the NOMINAL ENTRANCE FIELD SIZE. 6 Presentation of the ENTRANCE FIELD SIZE The presentation of the ENTRANCE FIELD SIZE shall include the following inform
