1、BRITISH STANDARD BS EN 25580:1992 ISO 5580:1985 Specification for Minimum requirements for industrial radiographic illuminators for non-destructive testing This European Standard EN 25580:1992 has the status of a British StandardBSEN 25580:1992 This British Standard, having been prepared under the d
2、irection of the General Mechanical Engineering Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on 15 June 1992 BSI 02-1999 The following BSI references relate to the work on this standard: Committee reference GME/23 Draft for approval 90/800
3、71 DC ISBN 0 580 20471 5 Cooperating organizations The European Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries. Austria Oesterreichisches Normungsinstitut Belgium Institut bel
4、ge de normalisation Denmark Dansk Standardiseringsraad Finland Suomen Standardisoimisliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standa
5、rds Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Swe
6、den Standardiseringskommissionen i Sverige Switzerland Association suisse de normalisation United Kingdom British Standards Institution Amendments issued since publication Amd. No. Date CommentsBSEN 25580:1992 BSI 02-1999 i Contents Page Cooperating organizations Inside front cover National foreword
7、 ii Foreword of EN 25580 2 1 Scope and field of application 3 2 Characteristics of radiographic illuminators 3 3 Determination of certain characteristics 4 4 Marking 4 5 Recommendations for use 4 Figure Light luminance measurement 5 National appendix NA (informative) Inside back coverBSEN 25580:1992
8、 ii BSI 02-1999 National foreword This British Standard has been prepared under the direction of the General Mechanical Engineering Standards Policy Committee and is the English language version of EN 25580:1992 “Non-destructive testing Industrial radiographic illuminators Minimum requirements” publ
9、ished by the European Committee for Standardization (CEN). EN 25580:1992 is identical with ISO 5580:1985 published by the International Organization for Standardization (ISO). National appendix NA gives the constitution of the committees responsible for UK participation in the preparation of this st
10、andard. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document co
11、mprises a front cover, an inside front cover, pages i and ii, theENtitle page, pages 2 to 6, 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.EU
12、ROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 25580 April 1992 UDC 620.179.152.05:620.186 Descriptors: Non-destructive tests, industrial radiography, radiographic illuminators, equipment specifications, screens: Display, luminance, divergence, lighting, optical measurements, marking English ver
13、sion Non-destructive testing Industrial radiographic illuminators Minimum requirements (ISO 5580:1985) Essais non destructifs Ngatoscopes utiliss en radiographie industrielle Exigences minimales (ISO 5580:1985) Zerstrungsfreie Prfung Betrachtungsgerte fr die industrielle Radiographie Minimale Anford
14、erungen (ISO 5580:1985) This European Standard was approved by CEN on 1992-03-27. CEN 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 alteration. Up-to-date lists and
15、bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibili
16、ty of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portu
17、gal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels CEN 1992 Copyright reserved to all CEN members Ref. No. EN 25580:1992 EEN25580:1992 BS
18、I 02-1999 2 Foreword In 1990, ISO 5580:1985 was submitted to the CEN Primary Questionnaire procedure. Following the positive result of this procedure, the CEN Technical Board, agreed to submit ISO5580:1985, without modifications, to Formal Vote. The result of the Formal Vote was positive. National s
19、tandards identical to this European Standard shall be published at the latest by92-10-31 and conflicting national standards shall be withdrawn at the latest by 92-10-31. In accordance with the CEN/CENELEC Common Rules, the following countries are bound to implement this European Standard: Austria, B
20、elgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EN25580:1992 BSI 02-1999 3 1 Scope and field of application This International Standard specifies the minimum requirements for industri
21、al illuminators used for viewing radiographs. The function of the illuminator is to allow the viewing of radiographs. The illuminator shall guarantee the same safety of personnel as an electric apparatus with maximum voltage, insulation and earthing which is required by corresponding safety standard
22、s of electrotechnics in each country where these are applied. 2 Characteristics of radiographic illuminators 2.1 Mechanical construction An illuminator consists of the housing with one of the sides being the viewing screen illuminated from the inside. This screen can itself be the diffusing screen.
23、This housing may also contain a system for thermal protection of the radiographs; this system may or may not be ventilated. For the viewing of wet radiographs, the illuminator shall be so designed as to prevent penetration of the liquid if the radiograph comes into contact with the screen. 2.2 Viewi
24、ng screen The screens shall be easy to clean and shall be made of a material which is resistant to scratching during cleaning processes recommended by the manufacturer and during film viewing. NOTE The screen may be a combination of elements, all of which should be resistant to heat in terms of defo
25、rmation and discoloration. The size of the screens shall allow the viewing of a radiograph without excessive glare reaching the eyes of the operator. Should the illuminator be used for viewing radiographs of different sizes, a system of covering masks shall be provided. 2.3 Luminance The screen lumi
26、nance required depends on the density of the radiographs. The following luminance levels are recommended for the perception of information at various density levels. The luminance (or brightness) of the illuminated radiograph shall be not less than: 30 cd/m 2for film densities 2,5 and, wherever poss
27、ible, approximately 100 cd/m 2or higher. These minimum values require the following screen luminance: NOTEThe illuminator may be provided with a device for continuous control of screen luminance. 2.4 Colour of light The colour of the light used to illuminate the radiograph is normally white. However
28、, in the case of a film with an emulsion type yielding a monocoloured image, light with adapted colours may be used if they have been recommended by the film manufacturers. 2.5 Diffusion of light If the illuminator has a diffusing screen, the light shall be sufficiently divergent so that both eyes o
29、f the observer receive rays from all parts of the screen. The diffusion factor s9 shall exceed 0,7 (see3.1). 2.6 Uniformity of illumination The screen shall be uniformly illuminated, the uniformity factor g being higher than 0,5 (see 3.2). 2.7 Disturbing light The housing, blinds and covering masks
30、shall be constructed in such a manner that no disturbing light hinders the viewing of the radiographs (see clause 3). 2.8 Anti-glare device Each illuminator shall be fitted with an anti-glare device which, by manual or automatic operation, prevents the operator from being subjected to excessive glar
31、e when the radiograph is removed. Film density Minimum screen luminance cd/m 2 1 1,5 2 2,5 3 3,5 4 4,5 300 1 000 3 000 10 000 10 000 30 000 100 000 300 000EN25580:1992 4 BSI 02-1999 2.9 Heating Appropriate precautions shall be taken to ensure that the temperature of the housing does not exceed60 C a
32、t the usual contact surfaces after1h of intermittent operation (50 % switched on with maximum of 15 s duration at an ambient temperature of 20 C). Further precautions shall be taken to ensure that a radiograph of density 2 does not warp after a continuous viewing time of 1 min and 1 h of intermitten
33、t operation of the illuminator. 3 Determination of certain characteristics All photometric measurements shall be carried out in a dark room. The luminance meter has to be used in the middle part of its measuring scale. Moreover, light escaping from the illuminator even when the viewing screen is com
34、pletely masked shall not affect the measurements. 3.1 Divergence and dispersion of light (of diffusing screens) The luminance shall be measured on a semi-circle, the centre of which is the centre of the screen and the diameter of which is approximately the same as the maximum dimension of the screen
35、, but at least50 cm. The luminance shall be measured with the aid of an appropriate luminance meter, the sensitive surface of which is a tangent to the curve of the circle (see the Figure). These measurements shall be made at angles of45(L 45 ), 20 (L 20 ) and 5 (L 5 ) related to the normal. The dif
36、fusion factor s9 shall be calculated according to the formula The measurements shall be made successively in both senses of rotation. 3.2 Uniformity of screen luminance The measurements shall be made with the aid of an illumination photometer or other suitable instrument. If the screen is rectangula
37、r, it shall be divided into squares, each side of the squares measuring 3,5 cm, the luminance of each being measured separately. If the screen is circular, the same basic procedure shall be followed. In both cases, the network of the squares shall be so arranged that the middle square is centred in
38、the middle of the screen. The average of the four highest and the average of the four lowest results shall be found, which give the average arithmetical values of the luminance L maxand L min . The uniformity factor g shall then be calculated according to the formula 3.3 Nominal power consumption Th
39、e nominal power consumption is the number of watts being consumed by the illuminator after it has been in continuous operation at full luminance for a minimum period of 30 min. 4 Marking A plate which is attached to the illuminator shall give the following information : a) nominal operating voltage
40、or permissible voltage range; b) nominal main frequency or permissible frequency range; c) whether for use with both direct and alternating current or only with one or the other; d) nominal power consumption; e) maximum luminance in candelas per square metre. 5 Recommendations for use Operating inst
41、ructions shall be provided with each illuminator to indicate: a) the operation of the apparatus; b) instructions for the mounting and replacement of lamps and screens; c) care and maintenance; d) safety precautions; e) frequency of checking luminance levels. s9 L 45 L 20 + 2 L 5 - = g L min L max -
42、=BSEN 25580:1992 BSI 02-1999 5 Figure Light luminance measurement6 blankBSEN 25580:1992 BSI 02-1999 National appendix NA (informative) The United Kingdom participation in the preparation of this European Standard was entrusted by the General Mechanical Engineering Standards Policy Committee (GME/-)
43、to Technical Committee GME/23 upon which the following bodies were represented: Aluminium Federation Associated Offices Technical Committee Association of Consulting Engineers BEAMA Ltd. BNF Metals Technology Centre British Airways British Chemical Engineering Contractors Association British Gas plc
44、 British Institute of Non-destructive Testing British Photographic Association British Steel Industry Electricity Industry in United Kingdom Health and Safety Executive Institute of Physics Institute of Quality Assurance Light Metal Founders Association Lloyds Register of Shipping Ministry of Defenc
45、e NAMAS Power Generation Contractors Association (BEAMA Ltd.) Royal Society of Chemistry Society of British Aerospace Companies Limited Society of Motor Manufacturers and Traders Limited Steel Casting Research and Trade Association The Welding InstituteBSI 389 Chiswick High Road London W4 4AL | | |
46、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BSI British Standards Institution BSI is the indepen
47、dent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions British Standards are updated by amendment or revision. Users of British Standards should make sure that they
48、possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the ide
49、ntity of which can be found on the inside front cover. Tel: 020 8996 9000. Fax: 020 8996 7400. BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards. Buying standards Orders for all BSI, international and foreign standards publications should be addressed to Customer Services. Tel: 020 8996 9001. Fax: 020 8996 7001. In response to orders for international standards, it is BSI policy to supply the BSI
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