1、 CENELEC ENxb1262-1 74 3404583 0350639 bT7 BRITISH STANDARD Characteristics of electro-optical X-ray image intensifiers for medical electrical equipment Part 1. Determination of the entrance field size The European Standard EN 61262-1 : 1994 has the status of a British Standard BS EN 61262-1 : 1995
2、IEC 1262-1 : 1994 CENELEC EN*b1262-1 94 = 3404583 0350620 319 BS EN 61262-1 : 1995 Amd. No. Committees responsible for this British Standard Date Rxt affected The preparation of this British Standard was entrusted to Echnical Committee HCC/72, Image intensifiers, upon which the following bodies were
3、 represented: Association of X-ray Equipment Manufacturers (BEAMA Ltd.) British Institute of Radiology College of Radiographers Institute of Physical Sciences in Medicine (Ipsm) This British Standard, having been prepared under the direction of the Health and Environment Sector Board (H/-), was publ
4、ished under the authority of the Standards Board and comes into effect on 15 April 1995 O BSI 1995 The following BSI references relate to the work on this standard: Committee reference HCC/72 Draft for comment 94/501341 DC ISBN O 680 23690 4 Amendments issued since publication CENELEC EN*b12b2-1 94
5、3404583 0350623 255 BS EN 61262-1 : 1995 Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN 61262-1 4 i CENELEC EN*b32b2-3 94 3404583 O350622 191 = BS EN 61262-1 : 1995 National foreword This British Standard has been prepared by Technical Committee HC
6、C/72 and is the English language version of EN 61262-1 : 1994 Medical electrical equipnent - Characteristics of electro-optical X-ray image intensifiers - Part 1 Determination of the entrance field size, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identi
7、cal with IEC 1262-1 : 1994 published by the International Electrotechnical Commission (IEC). It supersedes BS 6893: 1988, which is withdrawn.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,
8、 with which compliance can be tested, and definitions: in roman type. Explanations, advice, general statements, exceptions and references: in smaller type. %st procedures: in italic type. %rms defined in clause 3 of this standard and in annex A: in SMALL CAPITALS. For the purposes of this British St
9、andard, 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 obligations. Corresponding British Standard BS 6641 : 1985 Glossary of medical radiology tm ii CENELEC EN*bL262-L 74 3404583 0350623 028 EUROPEAN
10、 STANDARD NORME EUROPENNE EUROPISCHE NORM EN 61262-1 September 1994 ICs 11.040.50 Descriptors: Medical electrical equipment, image intensifier, X-ray, entrance field Supersedes HD 510 S1 : 1988 English version Medical electrical equipment - Characteristics of electro-optical X-ray image intensifiers
11、 Part 1: Determination of the entrance field size (IEC 1262-1 : 1994) Appareils lectromdicaux - Caractristiques des intensificateurs lectro-optiques dimage radiologique Rntgenbildverstrkern Partie 1: Dtermination de la dimension du Medizinische elektrische Gerte - Merkmale von elektronenoptischen Te
12、il 1 : Bestimmung der EingangsfeldgrBe champ dentre (CE1 1262-1 1994) (IEC 1262-1 : 1994) This European Standard was approved by CENELEC on 1994-07-05. CENELEC members are bound to comply with the CENICENELEC Internal Regulations which stipulate the conditions for giving this European Standard the s
13、tatus of a national standard without any alteration. 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, Germa
14、n). A version in any other language made by 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,
15、Finland, France, Germany, Greece, Iceland, Ireland, 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 Elektrotechnisch
16、e Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels O 1994 Copyright reserved to CENELEC members Ref. No. EN 61262-1 : 1994 E CENELEC EN*b12b2-2 94 w 3404583 0250624 Tb4 Page 2 EN 61262-1 : 1994 Foreword The text of document 62B(C0)112, as prepared by Sub-committee 62B: Diagnostic ima
17、ging equipment, of IEC Technical Committee 62: Electrical equipment in medical practice, was submitted to the IEC-CENELEC parallel vote in January 1994. The reference document was approved by CENELEC as EN 61262-1 on 5 July 1994. This European Standard replaces HD 510 S1 : 1988 The following dates w
18、ere fixed: - latest date of publication of an identical national standard (dop) 1995-07-01 - latest date of withdrawal of conflicting national standards (dow) 1995-07-01 For products which have complied with HD 510 S1 : 1988 before 1995-07-01, as shown by the manufacturer or by a certification body,
19、 this previous standard may continue to apply for production 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*bL2
20、62-L 9Ll 3404563 0150625 7TO Page 3 EN 61262-1 : 1994 CONTENTS FOREWORD 2 INTRODUCTION 4 Clause 1 scope . 5 2 Normative reference . 5 3 Terminology . 5 3.1 Definitions 5 3.2 Degree of requirements and reading instructions 6 4 Requirements 7 4.1 test set-up . 7 4.3 Input radiation . 7 4.4 TESTDEVICE
21、7 4.5 Measurement equipment . 7 4.2 X-RAY IMAGE INTENSIFIER . Opefating conditions . 7 5 Determination Of the USEFUL ENTRANCE FIELD SIZE and NOMINAL ENTRANCE FIELD SIZE 8 5.1 Preparation . 8 5.2 Measurement . 8 5.3 Corrections 8 5.4 Determination . 8 . 6 PfeSentatiOn Of the ENTRANCE FIELD SIZE . 9 7
22、 Statement of compliance 9 Annexes A Terminology . Index of terms 10 B Derivation Of the NOMINAL ENTRANCE FIELD SIZE 11 ZA Other international publications quoted in this standard with the references of the relevant European publications . 12 _ CENELEC ENrb1262-1 94 3404583 0350626 837 9 Page 4 EN 6
23、1262-1 : 1994 INTRODUCTION The ENTRANCE FIELD SIZE Of the ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIER can be specified in Several ways depending on the specific SED. Typically, the ENTRANCE FIELD SIZE is specified as a NOMINAL ENTRANCE FIELD SIZE O as a UCEFUL ENTRANCE FIELD SIZE. The SOURCE TO ENTRANCE
24、 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 the NOMINAL ENTRANCE FIELD SIZE and the USEFUL ENTRANCE FIELD SIZE are considered in this standard. The NOMINAL ENTRANCE FIELD SIZE S cal
25、culated from !weral USEFUL ENTRANCE FIELD SIZE measurements. Measurements of the USENL ENTRANCE FIUD SIZE in the magnification modes of the ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIER Will als0 be considered. CENELEC EN*bLZbZ-L 94 = 3404583 0350627 773 Page 5 EN 61262-1 : 1994 MEDICAL ELECTRICAL EQUIPME
26、NT - CHARACTERISTICS OF ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIERS - Part 1 : Determination of the entrance field size 1 scope This International Standard applies to ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIERS for medical use, as components of diagnostic X-RAY EQUIPMENT. This Intemational Standard descri
27、bes a method of determining the ENTRANCE FIELD SIZE of X-RAY IMAGE INTENSIFIERS. 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.
28、All standards are subject to revision, 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 Standard
29、s. IEC 788: 1984, Medical adioiogy - Terminology 3 Terminology 3.1 Definitions For the purposes of this International Standard, the foilowing 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 .I
30、 XRII: An abbreviation for ELECTRO-OPTICAL X-RAY IMAGE INTENSIFIER. 3.1.2 ENTRANCE 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 XR
31、II, the area in the ENTRANCE PLANE 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 ENTRANCE PLANE that can be used at a specified SED for the transmission of an X-RAY PATTERN. For an XRII wi
32、th more than one magnification mode, the ENTRANCE FIELD SIZE for each of the magnification 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 S
33、POT Of the X-RAY TUBE and the ENTRANCE PLANE Of the XRII. CENELEC EN*b12b2-L 94 3404583 0350628 bOT H Page 6 EN 61262-1 : 1994 3.1.6 CENT/? OF THE OUTPUT IMAGE: The centre Of the SmalleSt Circle circumscribing the OUTPUT IMAGE. 3.1.7 CENTRf OF THE ENTRANCE FIELD: That point in the ENTRANCE PLANE whi
34、ch 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 FIELD. 3.1.9 Not used 3.1.10 NOMINAL ENTRANCE FELD SUE: The ENTRANCE FIELD SIZE of the XRII that would be achieved with a parallel beam of IONIZ
35、ING RADIATION with the RmiAnoN SOURCE approaching infinity. 3.1.1 1 USEFUL ENTRANCE FIELD SIZE: The ENTRANCE FIELD SIZE measured at the ENTRANCE PLANE Of the XRII at a specified SED. 3.2 Degree of requirements and readhg instructions In this International Standard the auxiliary verb: - “shall“ - “Sh
36、old“ - “may“ implies that compliance with a requirement is mandatory for compliance with the standard; implies that compliance with a requirement is strongly recommended but is not mandatory for compliance with the standard; implies that compliance with a requirement is permitted to be accomplished
37、in a particular manner, for compliance with the standard; and the following words have the meaning: - “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; see
38、IEC 788, rm- 74-01. - “specified“ when used in combination with parameters or conditions: refers to a value or arrangement to be chosen for the purpose under consideration and indicated usually in ACCOMPANYING DOCUMENTS; see IEC 788, rm-74-02. - “designed for“ when used in standards to characterize
39、equipment, devices, components or arrangements: designates an intended and usually apparent purpose or use for the product. Page 7 EN 61262-1 : 1994 4 Requirements The instrumentation characteristics and the settings needed for the determination of the ENTRANCE FIELD SIZE are given here. 4.1 Test Se
40、t-up a) The SED shall be 100 cm I 1 cm. To determine the NOMINAL ENTRANCE FIELD SIZE, an additional measurement is required at an SED that is different from 100 cm. For this measurement, an SED of about 50 cm is recommended. b) The FOCAL SPOT Of the X-RAY TUBE shall be on the CENTRAL AXIS. C) The X-
41、RAY FIELD shall cover the ENTRANCE FIELD entirely. 4.2 X-RAY IMAGE ImNsi=m - 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 measurement shall be made for the largest spe
42、cified 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 that the image of the TEST DEVICE has a h
43、igh 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 shall not be larger than 2,O mm. b) The TEST
44、 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 for alignment of the TEST DEVICE in the
45、ENTRANCE FIELD. The telescope or microscope is als0 suggested for the determination of the actual meaSremeflt Of the ENTRANCE FIELD SIZE. CENELEC EN*61262-L 94 m 3404583 0350630 268 m Fage 8 EN 61262-1 : 1994 5 Determination Of the USEWL ENTRANCE RELD SIZE and NOMINAL ENTRANCE flELD SIZE 5.1 Prepara
46、tion a) The TEST DEVICE shall be placed in a plane as close as possible to, but not more than 10 mm in front of, and parallel to the ENTRANCE PLANE. b) The Centre Of the TEST DEVICE shall be on the CENiRAL AXIS. C) For measuring the USEFUL ENTRANCE FIELD SIZE the SED shall be adjusted to 100 cm f 1
47、Cm, see 4.1 a). 5.2 Measurement a) While the XRII is irradiated, determine the maximum dimension of the TEST DEVICE as seen in the om IMAGE with the SED at 100 cm i i cm. The use of a telescope or microscope to view the OUTPUT IMAGE is suggested to improve accuracy. In order to measure the USEFUL EN
48、TRANCE 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 magnification modes shall correspond to the same diameter of the XRII OUTPUT
49、IMAGE, as the one occurring in the normal mode of the XRII. b) Repeat the measurement as described in 5.2 a) with an SED of about 50 cm for the determination of the NOMINAL ENTRANCE FIELD SIZE. 5.3 Corrections Not used. 5.4 Determination 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: where d, S
