BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BSI Standards Publication AEROSPACE SERIES Specification for pan and 100° countersunk slotted head screws with ISO metric screw threads NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW raising standards worldwide™ `,,```,,,,````-`-`,,`,,`,`,,` - Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD Publishing and copyright information The BSI copyright notice displayed in this document indicates when the document was last issued © BSI 2010 ISBN 978 580 69783 ICS 49.030.20 The following BSI references relate to the work on this standard: Committee reference ACE/12 Draft for comment 10/30212967 DC Publication history First published August 1976 Second (current) edition, September 2010 Amendments issued since publication Text affected `,,```,,,,````-`-`,,`,,`,`,,` - Date Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 Contents Foreword iii Scope Normative references Quality assurance procedure Dimensions Freedom from defects 6 Screw threads 7 Surface roughness Mechanical tests Designation 10 10 Identification and marking 10 Bibliography 11 List of figures Figure – Basic dimensions: pan head screws Figure – Basic dimensions: 100° countersunk head screws Figure – Screw designation 10 List of tables Table – Sampling plan Table – Pan head screw dimensions Table – 100° countersunk head screw dimensions Table – Thread diameter/screw length codes Table – Materials `,,```,,,,````-`-`,,`,,`,`,,` - Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages to 12, an inside back cover and a back cover © BSI 2010 • Not for Resale i BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 `,,```,,,,````-`-`,,`,,` ii ã â BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS BRITISH STANDARD This page deliberately left blank Not for Resale BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 Foreword Publishing information This British Standard is published by BSI and came into effect on 30 September 2010 It was prepared by Technical Committee ACE/12, Aerospace fasteners and fastening systems A list of organizations represented on this committee can be obtained on request to its secretary Supersession This British Standard supersedes BS A 260, A 261, A 262, A 263, A 264, A 265:1976+A2:1982, which is withdrawn Information about this document The dimensional data is based on that agreed by Subcommittee ISO/TC20/SC4, Aircraft and space vehicles – Aerospace bolts and nuts This is a full revision of the standard, and introduces the following principal changes: a) Brinell hardness testing to BS 240 has been replaced by BS EN ISO 6506-1; b) Vickers hardness testing to BS 427 has been replaced by BS EN ISO 6507-1; c) Rockwell hardness testing to BS 891 has been replaced by BS EN ISO 6508-1; d) steel to BS 970 has been replaced by BS EN 10088-3; e) copper wire to BS 2873 has been replaced by BS EN 12166; f) reference to BS 4500 has been replaced by BS EN ISO 4759-1; g) tensile testing at ambient temperature to BS 4A has been replaced by BS EN 2002-1; h) reference to steel BS 3S 105 has been deleted; i) reference to steel BS S 154 has been added; j) reference to steel BS S 158 has been added; k) cadmium plating to DTD 904 has been replaced by Def Stan 03-19 and BS EN 2133; l) tin plating to Def Stan 03-8 has been replaced by BS 1872 Use of this document It has been assumed in the preparation of this British Standard that the execution of its provisions will be entrusted to appropriately qualified and experienced people, for whose use it has been produced CAUTION Screws conforming to BS A 260 and BS A 261 have cadmium as a plating material, which has been restricted and/or banned in many countries owing to environmental and health concerns Users should consult local officials if they have questions concerning the use of cadmium-plated parts © BSI 2010 • `,,```,,,,````-`-`,,`,,`,`,,` - Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale iii BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD Presentational conventions The provisions of this standard are presented in roman (i.e upright) type Its requirements are expressed in sentences in which the principal auxiliary verb is “shall” Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element Contractual and legal considerations This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application Compliance with a British Standard cannot confer immunity from legal obligations iv ã â BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS `,,```,,,,````-`-`,,`,,`,`,,` - Not for Resale BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 Scope This British Standard specifies requirements for pan and 100° countersunk slotted head screws with ISO metric threads The screws are primarily intended for use on non-structural aerospace applications Normative references The following referenced documents are indispensable for the application of this document For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies BS 1134-1, Assessment of surface texture – Part 1: Methods and instrumentation BS 1872, Specification for electroplated coatings of tin BS 3643-1, ISO metric screw threads – Part 1: Principles and basic data BS 3643-2, ISO metric screw threads – Part 2: Specification for selected limits of size BS A 100, Specification for general requirements for bolts and free running nuts of tensile strength not exceeding 1 249 MPa BS S 142, Specification for 1% chromium-molybdenum steel billets, bars, forgings and parts (900–1 100 MPa: limiting ruling section 40 mm) BS S 147, Specification for 0.5% nickel-chromium-molybdenum steel bars for the manufacture of forged bolts and forged nuts BS S 148, Specification for low nickel-chromium steel (bar for the manufacture of forged bolts only) BS S 154, Specification for 2½% nickel-chromium-molybdenum steel billets, bars, forgings and parts (880–1 080 MPa: limiting ruling section 150 mm) BS S 158, Specification for 1% chromium-molybdenum steel bars for the manufacture of forged bolts and forged nuts BS EN 2002-1, Metallic materials – Test methods – Part 1: Tensile testing at ambient temperature BS EN 2133, Cadmium plating of steels with specified tensile strength ≤1 450 MPa, copper, copper alloys and nickel alloys BS EN 10088-3:2005, Stainless steels – Part 3: Technical delivery conditions for semi‑finished products, bars, rods, wire, sections and bright products of corrosion resisting steels for general purposes BS EN 10263-5:2001, Steel rod, bars and wire for cold heading and cold extrusion – Part 5: Technical delivery conditions for stainless steels BS EN 12166:1998, Copper and copper alloys – Wire for general purposes BS EN ISO 4759-1:2001, Tolerances for fasteners – Part 1: Bolts, screws, studs and nuts – Product grades A, B and C BS EN ISO 6506-1, Metallic materials – Brinell hardness test – Part 1: Test method BS EN ISO 6507-1, Metallic materials – Vickers hardness test – Part 1: Test method `,,```,,,,````-`-`,,`,,`,`,,` - Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale © BSI 2010 • BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD BS EN ISO 6508-1, Metallic materials – Rockwell hardness test – Part 1: Test method (scales A, B, C, D, E, F, G, H, K, N, T) Defence Standard 03-19, Electro-deposition of cadmium 1) ASD-STAN TR 3775, Aerospace Series – Bolts and pins – materials 2) Quality assurance procedure The quality assurance procedure shall be in accordance with BS A 100 except that the samples for dimensional and non-destructive inspection shall be taken from each batch in accordance with the levels given in Table of this standard Table 1 Sampling plan Acceptable quality level (AQL) Inspection level 11 Inspection level S-1 1.0% Thread size Underhead radius Slot dimensions 2.5% Burrs and plating (visual) Head concentricity Slot form and position 4.0% Nominal length Other dimensions Head height (pan only) Head protrusion (countersunk only) Dimensions `,,```,,,,````-`-`,,`,,`,`,,` - The dimensions and tolerances of all screws shall conform to Table 2, Table 3, Table 4, Figure 1 and Figure 2, as relevant Unless otherwise specified, the dimensions shall apply after the application of the protective treatment 1) Available from www.dstan.mod.uk 2) Available from www.asd-stan.org ã â BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 Figure 1 Basic dimensions: pan head screws `,,```,,,,````-`-`,,`,,`,`,,` - Alternative end feature (as rolled) at manufacturer’s option Key Maximum incomplete lead of thread = × pitch Rad or chamfer at 45° Thread pitch diameter For all dimensions other than L, see Table For L, see Table Break sharp edges 0.1 to 0.4 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS â BSI 2010 ã Not for Resale BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD Figure 2 Basic dimensions: 100° countersunk head screws Alternative end feature (as rolled) at manufacturer’s option Key Maximum incomplete lead of thread = × pitch The maximum dimension between the end of the complete thread and the intersection between nominal diameter and cone of countersunk head shall be pitches + R (max.) Thread pitch diameter Gauge For all dimensions other than L, see Table For L, see Table Break sharp edges 0.1 to 0.4 4 • © BSI 2010 `,,```,,,,````-`-`,,`,,`,`,,` - Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS M2.5 × 0.45 M3 × 0.5 M4 × 0.7 M5 × 0.8 M6 × 1.0 25 30 40 50 60 4.6 3.9 3.0 2.3 1.9 1.4 3.6 2.9 2.5 1.8 1.4 0.9 0.6 12.0 10.0 8.0 6.0 5.0 4.0 3.2 11.7 9.8 7.8 5.8 4.8 3.8 3.0 Not for Resale M1.6 × 0.35 M2 × 0.4 M2.5 × 0.45 M3 × 0.5 M4 × 0.7 M5 × 0.8 M6 × 1.0 20 25 30 40 50 60 Dia × pitch ØD thread 16 Diameter code 3.6 2.9 2.5 1.8 1.4 0.9 0.6 `,,```,,,,````-`-`,,`,,`,`,,` - 4.6 3.9 3.0 2.3 1.9 1.4 1.1 max ØB 12.0 10.0 8.0 6.0 5.0 4.0 3.2 max ØA H 3.60 3.00 2.40 1.80 1.50 1.20 0.96 10.8 9.0 7.2 5.4 4.5 3.6 2.9 2.60 2.10 1.70 1.30 1.05 0.84 0.65 ref H 3.40 2.85 2.25 1.65 1.35 1.05 0.81 max ØC Table 3 100° countersunk head screw dimensions Dimensions in mm M2 × 0.4 20 1.1 max max Dia × pitch M1.6 × 0.35 ØA ØB ØD thread 16 Diameter code Table 2 Pan head screw dimensions Dimensions in mm 0.7 0.5 0.4 0.4 0.4 0.4 0.4 R radius 0.7 0.5 0.4 0.4 0.4 0.4 0.4 0.5 0.3 0.2 0.2 0.2 0.2 0.2 1.60 1.35 1.10 0.85 0.70 0.55 0.50 max 0.5 0.3 0.2 0.2 0.2 0.2 0.2 max R radius 0.60 0.50 0.40 0.30 0.25 0.20 0.16 max 2.40 2.00 1.60 1.20 1.00 0.80 0.64 max J radius T 1.20 1.00 0.80 0.60 0.50 0.35 0.30 0.3 0.3 0.3 0.3 0.3 0.3 0.3 N 1.90 1.50 1.20 1.00 0.80 0.70 0.60 N 1.90 1.50 1.20 1.00 0.80 0.70 0.60 1.65 1.25 1.05 0.85 0.65 0.55 0.45 1.65 1.25 1.05 0.85 0.65 0.55 0.45 max max 0.1 0.1 0.1 0.1 0.1 0.1 0.1 max S E 10.1 8.3 6.5 4.8 4.0 3.2 2.5 gauge ØV 1.44 1.20 0.96 0.72 0.60 0.48 0.38 0.80 0.71 0.63 0.50 0.41 0.33 0.28 max 1.44 1.20 0.96 0.72 0.60 0.48 0.38 max T W 0.20 0.18 0.14 0.10 0.10 0.07 0.06 Y 0.72 0.63 0.55 0.42 0.33 0.25 0.20 0.30 0.25 0.20 0.15 0.12 0.10 0.08 X 0.30 0.25 0.20 0.15 0.12 0.10 0.08 max X 2.7 2.1 1.8 1.5 1.5 1.5 1.5 max M BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 © BSI 2010 • BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD Table 4 Thread diameter/screw length codes Dimensions in mm Diameter/length code for thread diameter (ØD) A) (see Figure and Figure 2) Screw length L (see Figure and Figure 2) Nominal Tolerance B) M1.6 M2 M2.5 M3 M4 M5 M6 ±0.24 1604 2004 — — — — — 1605 2005 2505 — — — — 1606 2006 2506 3006 — — — 1608 2008 2508 3008 4008 — — 1610 2010 2510 3010 4010 5010 — — 2012 2512 3012 4012 5012 6012 14 — 2014 2514 3014 4014 5014 6014 16 — 2016 2516 3016 4016 5016 6016 18 — 2018 2518 3018 4018 5018 6018 — 2020 2520 3020 4020 5020 6020 22 — — 2522 3022 4022 5022 6022 24 — — 2524 3024 4024 5024 6024 26 — — — 3026 4026 5026 6026 28 — — — 3028 4028 5028 6028 30 — — — 3030 4030 5030 6030 — — — — 4035 5035 6035 40 — — — — 4040 5040 6040 45 — — — — — 5045 6045 50 — — — — — 5050 6050 — — — — — — 6055 — — — — — — 6060 ±0.29 10 12 20 35 55 ±0.35 ±0.42 ±0.50 ±0.60 60 A) The diameters/lengths tabulated are the preferred range Other diameter/length combinations may be agreed between the manufacturer and the purchaser B) Length (L) tolerance js15 in accordance with BS EN ISO 4759-1:2001, Product grade A Freedom from defects The screws shall be free from harmful defects, such as thread rolling laps between the nominal effective diameter and the minor diameter or any cracks NOTE Screws may be rejected at any time for faults in or revealed by manufacture, although they have been made from material previously passed for chemical composition and mechanical properties ã â BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS `,,```,,,,````-`-`,,`,,`,`,,` - Not for Resale BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 Screw threads 6.1 The screw threads shall be either cut or rolled for sizes up to and including M2.5 (diameter code 25) 6.2 The screw threads shall be rolled for sizes equal to and greater than M3 (diameter code 30) 6.3 Rolled screw threads shall be formed by a single rolling process after full heat treatment to achieve the specified mechanical properties of the material 6.4 The screw threads shall have the coarse thread form and tolerance 4h6h in accordance with BS 3643-1 and BS 3643-2 Surface roughness Unless otherwise specified, the surface roughness of all screws shall be Ra 3.2 when determined in accordance with BS 1134-1 `,,```,,,,````-`-`,,`,,`,`,,` - Mechanical tests 8.1 General These tests shall only be carried out on steel bar delivered in the softened or spheroidized condition for the production of screws which have forged heads and are subsequently heat treated A heat treatment batch shall consist of screws of the same nominal diameter produced from material of the same cast and heat treated together 8.2 8.2.1 Tensile test Initial tests 8.2.1.1 A tensile test shall be carried out on a length of bar of the same nominal diameter and from the same cast as that used for the production of the screws and which has been heat treated with the batch of screws 8.2.1.2 Tensile testing shall be carried out in accordance with BS EN 2002-1 and the mechanical properties shall conform to Table 8.2.1.3 It is permissible to use a full section test sample as the test piece; for these test pieces, the elongation shall be measured on a gauge length equal to five times the original diameter of the test piece 8.2.2 Retests If any test piece fails to conform to the requirements of Table 5: a) two further tensile tests shall be carried out in accordance with 8.2.1.2 and 8.2.1.3 The results of both tests shall conform to Table 5; or b) the batch shall be re-heat-treated and retested in accordance with 8.2.1 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS â BSI 2010 ã Not for Resale BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 8.3 8.3.1 BRITISH STANDARD Hardness test Initial tests 8.3.1.1 From each heat treatment batch (see 8.1), a minimum of 10 screws shall be hardness tested in accordance with BS EN ISO 6506-1 (Brinell) with an F/D2 of 30, BS EN ISO 6507‑1 (Vickers) or BS EN ISO 6508-1 (Rockwell) and the hardness shall be: a) 256 HBW to 330 HBW; or b) 270 HV to 348 HV; or c) 27 HRC to 37 HRC 8.3.1.2 All tests on the same batch shall be made by the same method and under the same conditions of loading 8.3.1.3 Unless a particular method is required by the purchaser, the hardness testing method used shall be at the discretion of the manufacturer 8.3.2 Retests If the hardness of any screw fails to conform to 8.3.1.1: a) the batch shall be re-heat-treated and retested in accordance with 8.3.1; or b) the batch shall be 100% hardness tested in accordance with 8.3.1 `,,```,,,,````-`-`,,`,,`,`,,` - 8 • © BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale Head style Pan 100° countersunk Pan 100° countersunk Pan 100° countersunk Basic BS no A260 A261 A262 A263 A264 A265 Table 5 Materials Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale Brass conforming to BS EN 12166:1998, CW508L – R700 or CW508L – R550 Corrosion-resisting steel rod or bar in condition +AT+C+AT+LC conforming to BS EN 10263-5:2001 -X3CrNiCu18-9-4 or -X3CrNiCuMo17-11-3-2 Corrosion-resisting steel bright bar in conditions 2H, 2B, 2G or 2P conforming to BS EN 10088-3:2005, -X2CrNi18-9, -X2CrNi19-11, -X5CrNi18-10, -X8CrNiS18-9, -X6CrNiTi18-10, -X4CrNiTi18-12 or -X5CrNiMo17-12-2; or Alloy steel to BS S 142, BS S 147, BS S 148, BS S 154, BS S 158 or ASD‑STAN TR 3775 (alloy steel classification 900 MPa) Type of material specification M1.5–M4: 620 MPa; M5 and M6: 550 MPa 650 MPa Not specified 28% 13% Elongation on 5.65 √So `,,```,,,,````-`-`,,`,,`,`,,` - Not specified 310 MPa 700 MPa min 900 MPa 0.2% proof stress Tensile strength Mechnical properties M1.5–M3: Cu/z/4/m; M4–M6: Cu/z/5/m Electro-deposition of tin in accordance with BS 1872 None Cadmium coated in accordance with Defence Standard 03-19 or BS EN 2133 Protective treatment BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 â BSI 2010 ã BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD Designation The screws shall be designated AXXX-XXXX 3), where XXX-XXXX is in accordance with Figure 3 Figure Screw designation 10 Identification and marking 10.1 Screws from M1.6 to M4 inclusive shall be identified by labelling the package Each package of screws shall have the complete part number designation (e.g A260-4008) and batch identification number or code clearly shown on each label 10.2 M4 screws shall have the manufacturer’s identification symbol applied to the upper surface of the head, randomly orientated to the slot, but offset from the axis of the screw by half the slot width 10.3 M5 and M6 screws shall have the last three digits of the basic BS number (e.g “260” from BS A 260) and the manufacturer’s identification applied to the upper surface of the head 10.4 The method of marking shall be selected from one of the following: a) by use of controlled pressure die stamping using a character marking die of a rounded tip form not less than 0.635 mm in height The depth of impression shall be kept to a minimum consistent with legibility and not more than 0.25 mm depth; b) integrally forged with characters that are not less than 0.635 mm in height; c) by microprocessor “controlled dot peen” with a spherical indenting stylus of 0.127 mm, an indentation depth of 0.025 4 mm to 0.05 mm for steel with a hardness less than 54 HRC and an indentation depth of not more than 0.076 mm for brass 10.5 All markings shall be applied to the screws prior to applying any required finish coating `,,```,,,,````-`-`,,`,,`,`,,` - 3) Marking a British Standard number (e.g A260) on or in relation to a product represents a manufacturer’s declaration of conformity, i.e a claim by or on behalf of the manufacturer that the product meets the requirements of the standard The accuracy of the claim is solely the claimant’s responsibility Such a declaration is not to be confused with third-party certification of conformity 10 ã â BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale BRITISH STANDARD BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 Bibliography Standards publications For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies BS 240, Method for Brinell hardness test and for verification of Brinell hardness testing machines 4) BS 427, Method for Vickers hardness test and for verification of Vickers hardness testing machines 4) BS 891, Methods for hardness test (Rockwell method) and for verification of hardness testing machines (Rockwell method) 4) BS 970, Specification for wrought steels for mechanical and allied engineering purposes 4) BS 2873, Specification for copper and copper alloys – Wire 4) BS 4500, Limits and fits – Guidance for system of cone (taper) fits and tolerances for cones from C = 1:3 to 1:500, lengths from mm to 630 mm and diameters up to 500 mm 4) BS 4A 4, Test pieces and test methods for metallic materials for aircraft – Metric units 4) `,,```,,,,````-`-`,,`,,`,`,,` - BS 3S 105, Specification for carbon steel (bar for the manufacture of forged bolts only) 4) DTD 904, Cadmium plating 4) Def Stan 03-8, Electro-deposition of tin 4) 4) Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS Referred to in Foreword only â BSI 2010 ã Not for Resale 11 BS 2A 260, 2A 261, 2A 262, 2A 263, 2A 264, 2A 265:2010 BRITISH STANDARD `,,```,,,,````-`-`,,`,,`,`,,` - 12 ã â BSI 2010 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS This page deliberately left blank Not for Resale `,,```,,,,````-`-`,,`,,`,`,,` - Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy No reproduction or networking permitted without license from IHS This page deliberately left blank Not for Resale British Standards Institution (BSI) BSI is the independent national body responsible for preparing British Standards and other standards-related publications, information and services It presents the UK view on standards in Europe and at the international level It is incorporated by Royal Charter `,,```,,,,````-`-`,,`,,`,`,,` - 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Uncontrolled Copy No reproduction or networking permitted without license from IHS Not for Resale