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BRITISH STANDARD BS EN 28630 3 1992 ISO 8630 3 1987 Incorporating Amendment Nos 0 and 1 Guide to Construction and use of 130 mm (5 25 in) flexible disk cartridges for data interchange, using modified[.]

BRITISH STANDARD Guide to Construction and use of 130 mm (5.25 in) flexible disk cartridges for data interchange, using modified frequency modulation recording at 13 262 ftprad, on 80 tracks each side — Part 3: Track format B for 80 tracks The European Standard EN 28630-3:1992 has the status of a British Standard UDC 681.327.63 BS EN 28630-3:1992 ISO 8630-3: 1987 Incorporating Amendment Nos and BS EN 28630-3:1992 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Information Systems Technology Standards Committee (IST/-) to Technical Committee IST/4, upon which the following bodies were represented: Association for Payment Clearing Services British Computer Society British Telecommunications plc Business Equipment and Information Technology Association Department of Trade and Industry (National Physical Laboratory) HM Treasury (Central Computer and Telecommunications Agency) Institute of Administrative Management Institute of Quality Assurance Institution of Electrical Engineers Institution of Electronic and Radio Engineers Institution of Mechanical Engineers National Computing Centre Ltd Post Office Coopted members This British Standard, having been prepared under the direction of the Information Systems Technology Standards Committee, was published under the authority of the Board of BSI and comes into effect on 30 September 1988 © BSI 02-2000 The following BSI references relate to the work on this standard: Committee reference IST/4 Draft for comment 87/66414 DC ISBN 580 16524 Amendments issued since publication Amd No Date of issue 7324 December 1992 8193 June 1994 Comments Indicated by a sideline in the margin BS EN 28630-3:1992 Contents Committees responsible National foreword Foreword Introduction Scope and field of application Conformance References General requirements Track layout Coded representation of data Annex A EDC implementation Annex B Procedure and equipment for measuring flux transition spacing Annex C Data separators for decoding MFM recording Figure Figure Figure Figure Figure Table Table Publications referred to © BSI 02-2000 Page Inside front cover ii 3 3 7 5 Inside back cover i BS EN 28630-3:1992 National foreword This Part of BS 6957, prepared under the direction of the Information Systems Technology Standards Committee, is identical with ISO 8630-3:1987 “Information processing — Data interchange on 130 mm (5 25 in) flexible disk cartridges using modified frequency modulation recording at 13 262 ftprad, on 80 tracks on each side — Part 3: Track format B for 80 tracks ”, published by the International Organization for Standardization (ISO) In 1992 the European Committee for Standardization (CEN) accepted ISO 8630-3:1987 as European Standard EN 28630-3:1992 As a consequence of implementing the European Standard this British Standard is renumbered as BS EN 28630-3 and any reference to BS 6957-3 should be read as a reference to BS EN 28630-3 In 1993 CEN accepted ISO Technical Corrigendum 1:1992 to ISO 8630-3 as Amendment 1:1993 to EN 28630-3 The purpose of this standard is to define those characteristics necessary for successful data interchange using magnetic disks The information contained is intended as a guide to writing complete specifications for manufacture, purchasing and/or testing The text of the International Standard does not accord with the recommendations for drafting product specifications given in the ISO Directives, or in BS 0-3, but the BSI Technical Committee considers the text is useful as a guide when disks are being described or specified For this reason this Part of BS 6957 has a different title from the International Standard; it is issued as a British Standard guide, and it should only be used as such It should not be used on its own as a British Standard product specification, and, in particular, no claims of compliance with this Part of BS 6957 should be made Terminology and conventions The text of the International Standard has been approved as suitable for publication as a British Standard without deviation Some terminology and certain conventions are not identical with those used in British Standards; attention is drawn especially to the following For metric units the comma has been used as a decimal marker In British Standards it is current practice to use a full point on the baseline as the decimal marker Wherever the words “part of ISO 8630” and “ISO 8630” appear, referring to this standard, they should be read as “Part of BS 6957” and “BS 6957” respectively Cross-references International Standard ISO 646:1983 Corresponding British Standard BS 4730:1985 Specification for UK 7-bit coded character set ISO 2022:1986 (Identical, exercising national options) BS 6856:1987 Specification for code extension ISO 4873:1986 (Identical) BS 6006:1987 Specification for structure and rules for ISO 6429:1983 (Identical) DD 94:1984 Definition of additional control functions techniques for United Kingdom 7-bit and 8-bit coded character sets implementation of United Kingdom 8-bit coded character set for character-imaging devices for information processing, using extended ISO 7-bit and 8-bit coded character sets (Identical) BS 6957 Guide to construction and use of 130 mm (5 25 in) flexible disk cartridges for data interchange, using modified frequency modulation recording at 13 262 ftprad, on 80 tracks on each side ii © BSI 02-2000 BS EN 28630-3:1992 International Standard ISO 8630-1:1987 ISO 8630-2:1987 ISO 9293:1988 Corresponding British Standard Part 1:1988 Dimensional, physical and magnetic characteristics (Identical) Part 2:1988 Track format A for 77 tracks (Identical) BS 6542 File structure and labelling of flexible disk cartridges for information interchange Part 2:1988 Specification for variable file allocation structure (Identical) 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 comprises a front cover, an inside front cover, pages i to iv, the EN title page, pages to 10, 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 © BSI 02-2000 iii iv blank EN 28630-3 EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM August 1992 + A1 November 1993 UDC 681.327.63 Descriptors: Data processing, information interchange, data recording devices, magnetic disks, flexible disks, flexible disk cartridges, recording tracks, trackformat, specifications English version Information processing — Data interchange on 130 mm (5.25 in) flexible disk cartridges using modified frequency modulation recording at 13 262 ftprad, on 80 tracks each side Part 3: Track format B for 80 tracks (includes amendment A1:1993) (ISO 8630-3:1987) Informationsverarbeitung — Datenaustausch Traitement de l’information — Échange de données sur cartouches disquettes de 130 mm auf 130 mm (5,25 in) Disketten mit modifizierter Wechseltaktschrift bei (5,25 in) utilisant un enregistrement zweiseitiger Aufzeichnung modulation de fréquence modifiée (MFM) mit 13 262 Flusswechsel/rad und 80 Spuren 13 262 ftprad sur 80 pistes sur chaque face auf jeder Seite Partie 3: Schéma de piste B pour 80 pistes Teil 3: Spurformat B für 80 Spuren (inclut l’amendement A1:1993) (enthält Änderungen A1:1993) (ISO 8630-3:1987) (ISO 8630-3:1987) This European Standard was approved by CEN on 1992-08-13 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 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 responsibility 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, Portugal, Spain, Sweden, Switzerland and United Kingdom CEN European Committee for Standardization Comité Européen de Normalisation Europäisches Komitee für Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels © 1992 Copyright reserved to CEN members Ref No EN 28630-3:1992 + A1:1993 E EN 28630-3:1992 Foreword The Technical Board has decided to submit the International Standard 8630-3:1987 Information processing — Data interchange on 130 mm (5 25 in) flexible disk cartridges using modified frequency modulation recording at 13 262 ftprad, on 80 tracks each side — Part 3: Track format B for 80 tracks for Formal Vote The standard was accepted This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 1993 and conflicting national standards shall be withdrawn at the latest by February 1993 According to the CEN/CENELEC Common Rules the following countries are bound to implement this standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom Foreword to Amendment A1 The Technical Board decided to submit the draft Amendment Information processing — Data interchange on 130 mm (5 25 in) flexible disk cartridges using modified frequency modulation recording at 13 262 ftprad, on 80 tracks each side — Part 3: Track format B for 80 tracks (ISO 8630-3:1987, Technical Corrigendum 1:1992), to the Unique Acceptance Procedure (UAP) The result of the Unique Acceptance Procedure was positive For the time being, this document exists only in English This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 1994, and conflicting national standards shall be withdrawn at the latest by May 1994 In accordance with the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom © BSI 02-2000 EN 28630-3:1992 Introduction ISO 8630 specifies the characteristics of 130 mm (5.25 in) flexible disk cartridges recorded at 13 262 ftprad, using modified frequency modulation (MFM) recording, on 80 tracks on each side ISO 8630-1 specifies the dimensional, physical and magnetic characteristics of the cartridge, so as to provide physical interchangeability between data processing systems ISO 8630-2 specifies an alternative track format for data interchange ISO 8630-1 and ISO 8630-3, together with the labelling scheme specified in ISO 9293, provide for full data interchange between data processing systems Scope and field of application This part of ISO 8630 specifies the quality of recorded signals, the track layout, and a track format to be used on 130 mm (5.25 in), 13 262 ftprad flexible disk cartridges intended for data interchange between data processing systems NOTE Numeric values in the SI and/or Imperial measurement system in this part of ISO 8630 may have been rounded off and therefore are consistent with, but not exactly equal to, each other Either system may be used, but the two should be neither intermixed nor re-converted The original design was made using Imperial units and further developments were made using SI units Conformance A flexible disk cartridge shall be in conformance with ISO 8630 when it meets all the requirements of parts and of ISO 8630 NOTE ISO 9293 specifies a field in the volume label References ISO 646, Information processing — ISO 7-bit coded character set for information interchange ISO 2022, Information processing — ISO 7-bit and 8-bit coded character sets — Code extension techniques ISO 4873, Information processing — ISO 8-bit code for information interchange — Structure and rules for implementation ISO 6429, Information processing — ISO 7-bit and 8-bit character sets — Additional control functions for character-imaging devices ISO 9293, Information processing — Volume and file structure of flexible disk cartridges for information interchange 1) Flux transitions © BSI 02-2000 General requirements 4.1 Mode of recording The mode of recording shall be Modified Frequency Modulation (MFM) for which the conditions are a) a flux transition shall be written at the centre of each bit cell containing a ONE; b) a flux transition shall be written at each cell boundary between consecutive bit cells containing ZEROs Exceptions to this are defined in 4.12 4.2 Track location tolerance of the recorded flexible disk cartridge The centrelines of the recorded tracks shall be within ± 0,042 mm (± 0.001 67 in) of the nominal positions, over the range of operating environment specified in ISO 8630-1 4.3 Recording offset angle At the instant of writing or reading a magnetic transition, the transition shall have an angle of ° ± 18 with the radius ½ NOTE As tracks may be written and overwritten at extremes of the tolerances given in 4.2 and 4.3 , a band of old information may be left at one edge of the newly written data and would constitute unwanted noise when reading It is therefore necessary to trim the edges of the tracks by erasure after writing 4.4 Density of recording 4.4.1 The nominal density of recording shall 1) be 13 262 ftprad The resulting nominal bit cell length is 75,5 4rad 4.4.2 The long-term average bit cell length shall be the average bit cell length measured over a sector It shall be within ± 3,0 % of the nominal bit cell length 4.4.3 The short-term average bit cell length, referred to a particular bit cell, shall be the average of the lengths of the preceding eight bit cells It shall be within ± % of the long-term average bit cell length 4.5 Flux transition spacing (See Figure 1) The instantaneous spacing between flux transitions may be influenced by the reading and writing process, the bit sequence recorded (pulse crowding effects) and other factors The locations of the transitions are defined as the locations of the peaks in the signal when reading Tests should be carried out using a peak-sensing read amplifier (see Annex B and Annex C) 4.5.1 The spacing between the flux transitions in a sequence of ONEs shall be between 80 % and 120 % of the short-term average bit cell length per radian EN 28630-3:1992 4.5.2 The spacing between the flux transition for a ONE and that between two ZEROs preceding or following it shall be between 130 % and 165 % of the short-term average bit cell length 4.5.3 The spacing between the flux transitions of two ONEs surrounding a ZERO shall lie between 185 % and 225 % of the short-term average bit cell length 4.6 Average Signal Amplitude For each side the Average Signal Amplitude on any track (see ISO 8630-1) of the interchanged flexible disk cartridge shall be less than 160 % of SRA1 f and more than 40 % of SRA2f 4.7 Byte A byte is a group of eight bit-positions, identified B1 to B8 The bit in each position is a ZERO or a ONE 4.8 Sector All tracks shall be divided into 15 sectors of 512 bytes A pair of tracks, one on each side of the disk, having the same track number 4.10 Cylinder Number The Cylinder Number shall be a two-digit number identical with the track number of the tracks of the cylinder The data capacity of a track shall be 680 bytes 4.12 Hexadecimal notation Hexadecimal notation shall be used hereafter to denote the following bytes: (00) for (B8 to B1) = 00000000 (01) for (B8 to B1) = 00000001 (02) for (B8 to B1) = 00000010 4.13 Error Detection Characters (EDC) The two EDC bytes are hardware-generated by shifting serially the relevant bits, specified later for each part of the track, through a 16-bit shift register described by the generator polynomial: X16 + X12 + X5 + (See also Annex A.) Track layout After formatting, there shall be 15 usable sectors on each track The layout of each track shall be as shown in Figure 5.1 Index Gap 4.9 Cylinder 4.11 Data capacity of a track (4E) for (B8 to B1) = 01001110 (FE) for (B8 to B1) = 11111110 (FB) for (B8 to B1) = 11111011 (A1) 2) for (B8 to B1) = 10100001 In byte (A1) 2) the boundary transition between B3 and B4 is missing At nominal density, this field shall comprise not less than 32 bytes and not more than 146 bytes, the content of which is not specified except that it shall not contain an (A1)*-byte Writing the Index Gap is started when the index hole is detected Any of the first 16 bytes may become ill-defined due to subsequent overwriting 5.2 Sector Identifier The layout of this field shall be as shown in Table 5.2.1 Identifier Mark This field shall comprise 16 bytes: 12 (00)-bytes (A1)*-bytes (FE)-byte Figure 2) Flux transitions per radian © BSI 02-2000 EN 28630-3:1992 Table Sector Identifier Identifier Mark 12 bytes (00) bytes (A1)* Address Identifier byte (FE) Track Address C byte 5.2.2 Address Identifier This field shall comprise bytes Side byte (00) or (01) This field shall comprise bytes: a) Cylinder Number (C) This field shall specify in binary notation the Cylinder Number from 00 for the outermost cylinder to 79 for the innermost cylinder b) Side Number (Side) This field shall specify the side of the disk On side it shall be (00) on all tracks On side it shall be (01) on all tracks 5.2.2.2 Sector Number (S) The 3rd byte shall specify in binary notation the Sector Number from 01 for the first sector to 15 for the last sector The sectors may be recorded in any order of their Sector Numbers 5.2.2.3 4th byte The 4th byte shall always be a (02)-byte These two bytes shall be generated as defined in 4.13 using the bytes of the Sector Identifier starting with the first (A1)*-byte (see 5.2.1 ) of the Identifier Mark and ending with the 4th byte (see 5.2.2.3 ) of the Address Identifier If the EDC is incorrect, then the sector is defective ISO 9293 specifies the handling of defective sectors © BSI 02-2000 byte EDC byte (02) bytes Figure 5.3 Identifier Gap 5.2.2.1 Track Address 5.2.2.4 EDC S This field shall comprise 22 initially recorded (4E)-bytes These bytes may have become ill-defined due to overwriting 5.4 Data Block The layout of this field shall be as given in Table Table Data Block Data Mark Data Field 12 bytes bytes (00) (A1)* byte (FB) EDC 512 bytes bytes 5.4.1 Data Mark This field shall comprise 16 bytes: 12 (00)-bytes (A1)*-bytes (FB)-byte 5.4.2 Data Field This field shall comprise 512 bytes If it comprises less than the requisite number of data bytes, the remaining positions shall be filled with (00)-bytes 5.4.3 EDC These two bytes shall be generated as defined in 4.13 using the bytes of the Data Block starting with the first (A1)*-byte of the Data Mark (see 5.4.1 ) and ending with the last byte of the Data Field (see 5.4.2 ) EN 28630-3:1992 If the EDC is incorrect, then the sector is defective 6.2 Coding methods ISO 9293 specifies the handling of defective sectors 6.2.1 When the coding method requires it, the Data 5.5 Data Block Gap Field shall be regarded as an ordered sequence of 8-bit bytes This field shall comprise 84 initially Within each byte the bit positions shall be identified recorded (4E)-bytes These bytes may have by B8 to B1 The high-order bit shall be recorded in become ill-defined due to overwriting position B8 and the low-order bit in position B1 The The Data Block Gap is recorded after each Data sequence of recording shall be high-order bit first Block and it precedes the following Sector Identifier When the data is encoded according to an 8-bit code, After the last Data Block, it precedes the Track Gap the binary weights of the bit positions shall be as 5.6 Track Gap shown in Figure This field shall follow the Data Block Gap of the last sector (4E)-bytes are written until the Index hole is B8 B7 B6 B5 B4 B3 B2 B1 detected, unless it has been detected during writing Bit Position Binary Weights 128 64 32 16 of the last Data Block Gap, in which case there shall be no Track Gap Figure When the data is encoded according to a 7-bit code, Coded representation of data bit position B8 shall contain bit ZERO, and the data 6.1 Standards shall be encoded in bit positions B7 to B1, using the same binary weights as shown in Figure The contents of the Data Field shall be recorded and 6.2.2 When the coding method requires it, the Data interpreted according to the relevant International Standards for the coding of information, for example Field shall be regarded as an ordered sequence of bit positions, each containing a bit ISO 646, ISO 2022 or ISO 4873 © BSI 02-2000 EN 28630-3:1992 Annex A EDC implementation (This annex does not form part of the standard.) Figure shows the feedback connections of a shift register which may be used to generate the EDC bytes Prior to operation, all positions of the shift register are set to ONE Input data are added (exclusive OR) to the contents of position C 15 of the register to form a feedback This feedback is in its turn added (exclusive OR) to the contents of position C and position C 11 On shifting, the outputs of the exclusive OR gates are entered respectively into positions C 0, C and C 12 After the last data bit has been added, the register is shifted once more as specified above The register then contains the EDC bytes If further shifting is to take place during the writing of the EDC bytes, the control signal inhibits exclusive OR operations To check for errors when reading, the data bits are added into the shift register in exactly the same manner as they were during writing After the data, the EDC bytes are also entered into the shift register as if they were data After the final shift, the register contents will be all ZERO if the record does not contain errors Figure Annex B Procedure and equipment for measuring flux transition spacing (This annex does not form part of the standard.) B.1 General This annex specifies equipment and a procedure for measuring flux transition spacing on 130 mm (5.25 in) flexible disk cartridges using MFM recording at 13 262 ftprad on both sides B.2 Format The disk to be measured shall be written by the disk drive for data interchange use Testing shall be done on tracks 00 and 76 on both sides On all test tracks the test patterns 11011011 (DB) and 11011100 (DC) shall be written repeatedly B.3 Test equipment B.3.1 Disk drive The disk drive shall have a rotational speed of 360 r/min, with a tolerance of ± r/min, averaged over one revolution The average angular speed, taken over 32 4s, shall not deviate by more than 0,5 % from the speed averaged over one revolution B.3.2 Head B.3.2.1 Resolution The head shall have an absolute resolution of 55 % to 65 % at track 76 on side and at track 68 on side 1, using the reference material RM 8630, applying the calibration factor of the reference material, and recording with the appropriate test recording current The resonant frequency of the head shall be at least 500 000 Hz © BSI 02-2000 EN 28630-3:1992 The resolution shall not be adjusted by varying the load impedance of the head The resolution shall be measured at the output of the amplifier defined in B.3.3.1 B.3.2.2 Offset angle The head shall have a gap offset angle of ° ± with the disk radius on the testing drive B.3.2.3 Contact ½ Care shall be taken that the heads are in good contact with the media during the tests B.3.3 Read channel B.3.3.1 Read amplifier The read amplifier shall have a flat response from 000 to 375 000 Hz within ± dB, and amplitude saturation shall not occur B.3.3.2 Peak sensing amplifier Peak sensing shall be carried out by a differentiating and limiting amplifier B.3.4 Time interval measuring equipment The time interval counter shall be able to measure 4s to at least ns resolution A triggering oscilloscope may be used for this purpose B.4 Procedure for measurement B.4.1 Flux transition spacing measurement The transition locations shall be measured by the locations of the peaks in the signal when reading The flux transition spacing shall be measured by the pulse timing intervals after the read channel amplifier defined in B.3.3 B.4.2 Flux transition spacing for all tracks Measure time intervals t1 to t5 as shown in Figure t1 and t2 correspond to sub-clause 4.5.1 t3 and t4 correspond to sub-clause 4.5.2 t5 corresponds to sub-clause 4.5.3 Figure © BSI 02-2000 EN 28630-3:1992 Annex C Data separators for decoding MFM recording (This annex does not form part of the standard.) C.1 On track 00, side the two-frequency recording results in nominal flux transition periods of t for a ONE cell t for a ZERO cell where t = 4s The data separator shall be capable of resolving a difference of 4s This can be achieved satisfactorily by the use of a digital data separator, or one using a fixed timer C.2 On all other tracks the MFM recording method gives nominal flux transition spacings of t for the patterns 11 or 000 t/2 for the patterns 10 or 01 t for the pattern 101 The data separator should be capable of resolving a difference of 4s To achieve this with a low error rate, the separator cannot operate on a fixed period but should follow changes in the bit cell length It is recognized that various techniques may be developed to achieve dynamic data separation; with present technology only an analogue data separator based on a phase-locked oscillator can provide the necessary reliability © BSI 02-2000 10 blank BS EN 28630-3:1992 Publications referred to See national foreword © BSI 02-2000 BS EN 28630-3:1992 ISO 8630-3: 1987 BSI — British Standards Institution BSI is the independent 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 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 identity 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 implementation of those that have been published as British Standards, unless otherwise requested Information on standards BSI provides a wide range of information on national, European and international standards through its Library and its Technical Help to Exporters Service Various BSI electronic information services are also available which give details on all its products and services Contact the Information Centre Tel: 020 8996 7111 Fax: 020 8996 7048 Subscribing members of BSI are kept up to date with standards developments and receive substantial discounts on the purchase price of standards For details of these and other benefits contact Membership Administration Tel: 020 8996 7002 Fax: 020 8996 7001 Copyright Copyright subsists in all BSI publications BSI also holds the copyright, in the UK, of the publications of the international standardization bodies Except as permitted under the Copyright, Designs and Patents Act 1988 no extract may be reproduced, stored in a retrieval system or transmitted in any form or by any means – electronic, photocopying, recording or otherwise – without prior written permission from BSI This does not preclude the free use, in the course of implementing the standard, of necessary details such as symbols, and size, type or grade designations If these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained BSI 389 Chiswick High Road London W4 4AL If permission is granted, the terms may include royalty payments or a licensing agreement Details and advice can be obtained from the Copyright Manager Tel: 020 8996 7070

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