BS EN 16602-70-21:2014 BSI Standards Publication Space product assurance — Flammability testing for the screening of space materials BS EN 16602-70-21:2014 BRITISH STANDARD National foreword This British Standard is the UK implementation of EN 16602-70-21:2014 It supersedes BS EN 14090:2002 which is withdrawn The UK participation in its preparation was entrusted to Technical Committee ACE/68, Space systems and operations A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application © The British Standards Institution 2014 Published by BSI Standards Limited 2014 ISBN 978 580 84601 ICS 13.220.40; 49.025.01; 49.140 Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2014 Amendments issued since publication Date Text affected BS EN 16602-70-21:2014 EN 16602-70-21 EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM October 2014 ICS 13.220.40; 49.025.01; 49.140 Supersedes EN 14090:2002 English version Space product assurance - Flammability testing for the screening of space materials Assurance produit des projets spatiaux - Essai de flammabilité pour la sélection des matériaux d'un projet spatial Raumfahrtproduktsicherung - Brennverhaltenstest für die Auswahl von Raumfahrtmaterialien This European Standard was approved by CEN on 11 April 2014 CEN and 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 alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN and CENELEC 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 and CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels © 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved worldwide for CEN national Members and for CENELEC Members Ref No EN 16602-70-21:2014 E BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Table of contents Foreword Scope Normative references Terms, definitions and abbreviated terms 3.1 Terms from other standards 3.2 Terms specific to the present standard .7 3.3 Abbreviated terms Principles 4.1 Test methods 4.2 Screening tests 4.2.1 Overview .8 4.2.2 Screening Test 1: Upward propagation test 4.2.3 Screening Test 2: Standard test method for the determination of the oxygen concentration limit during the combustion of polymer materials .9 4.2.4 Screening Test 3: Electrical wire insulation flammability test method 4.3 Configuration test .9 4.4 Additional tests Requirements 10 5.1 5.2 Test procedure .10 5.1.1 Preparatory conditions 10 5.1.2 Test methods 11 Quality assurance 20 5.2.1 Data 20 5.2.2 Nonconformance .21 5.2.3 Calibration 21 5.2.4 Traceability .21 Annex A (normative) Test report – DRD 22 Annex B (informative) Test procedures 25 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Annex C (informative) Preparation and qualification of chemical igniters 30 Annex D (informative) Graphical information 38 Bibliography 47 Figures Figure D-1 Diagram of the equipment used to determine the oxygen concentration limit 38 Figure D-2 Frame used to fix the sample 39 Figure D-3 Sample holder 40 Figure D-4 Sample holder 41 Figure D-5 : Samples from thermoplastic polymer materials 42 Figure D-6 : Test set up for flammability of electric wires under heated wire conditions at 25 % by volume oxygen 43 Figure D-7 General arrangement of modified burner and flame dimensions 45 Figure D-8 General arrangement of apparatus for flammability test 46 Tables Table D-1 : Description of test equipment as per Figure D-6 43 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Foreword This document (EN 16602-70-21:2014) has been prepared by Technical Committee CEN/CLC/TC “Space”, the secretariat of which is held by DIN This standard (EN 16602-70-21:2014) originates from ECSS-Q-ST-70-21C 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 April 2015, and conflicting national standards shall be withdrawn at the latest by April 2015 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights This document supersedes EN 14090:2002 This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association This document has been developed to cover specifically space systems and has therefore precedence over any EN covering the same scope but with a wider domain of applicability (e.g : aerospace) According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Scope This Standard defines a multitest procedure for the determination of the flammability characteristics of nonmetallic materials under a set of closely controlled conditions The test procedure covers both individual materials and materials used in configuration This Standard describes a series of tests to provide data for aid in the evaluation of the suitability of materials for use in a space vehicle crew compartment The data obtained are in respect to the ease of ignition and the flame propagation characteristics of materials All nonmetallic materials are inherently flammable, the degree to which this is true is dependant on the chemical nature of the material itself and the environment to which the material is exposed In the closed environment of a manned spacecraft this can lead to a potentially dangerous situation and close control is therefore required This standard may be tailored for the specific characteristics and constrains of a space project in conformance with ECSS-S-ST-00 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this ECSS Standard For dated references, subsequent amendments to, or revision of any of these publications not apply However, parties to agreements based on this ECSS Standard are encouraged to investigate the possibility of applying the more recent editions of the normative documents indicated below For undated references, the latest edition of the publication referred to applies EN reference Reference in text Title EN 16601-00-01 ECSS-S-ST-00-01 ECSS system - Glossary of terms EN 16602-10-09 ECSS-Q-ST-10-09 Space product assurance - Nonconformance control system EN 16602-70 ECSS-Q-ST-70 Space product assurance - Materials, mechanical parts and processes DIN 50050-1:1986 Testing of materials; burning behaviour of materials; small burning cabinet ISO 6941:1984 Textile fabrics - Burning behaviour - Measurement of flame spread properties of vertically oriented specimens BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Terms, definitions and abbreviated terms 3.1 Terms from other standards For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01 apply, in particular for the following terms: flammability For the purpose of this Standard, the terms and definitions from ECSS-Q-ST-70 apply 3.2 Terms specific to the present standard 3.2.1 oxygen concentration limit during the combustion of polymeric materials minimum volumetric amount of oxygen contained in the nitrogenoxygen mixture, in the presence of which the material can still combust after ignition from the bottom NOTE It is expressed as a percentage and determined using the equation: n Clim = NOTE 3.3 ∑C i =1 lim ,i [3-1] n i.e the arithmetic average of the concentration limit calculated as a function of the results of unit measurements of (Clim,i) Abbreviated terms For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01 and the following apply: Abbreviation Meaning Clim minimum volumetric concentration of oxygen contained in an oxygennitrogen mixture, in the presence of which a material can still combust after ignition from the bottom HMT hexamethylenetetramine BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Principles 4.1 Test methods Four test methods are included within this Standard They can be divided into two different categories: 4.2 • Screening tests (see clause 4.2), and • Configuration tests (see clause 4.3) Screening tests 4.2.1 Overview These are the prime tests to be performed on a material to assess its basic acceptability or otherwise with respect to flammability They are designed to test the material under worst case test conditions, with respect to, for instance, environment, use, or thickness The following two tests form the basis for acceptance or otherwise of most nonmetallic materials but are very different in the data generated: a Test 1: Upward propagation test b Test 2: Standard test method for the determination of the oxygen concentration limit during the combustion of polymer materials The choice of which test method is used is dependant on the project concerned and is specified within the business agreement Test “Electrical wire insulation flammability test method” is related specifically to wire insulation materials Materials which meet the requirements of these tests can be considered for general application, within the constraints of the test conditions used 4.2.2 Screening Test 1: Upward propagation test The purpose of this test is to determine the flammability characteristics of candidate materials supplied to a standard format when exposed to an ignition source applied at the bottom edge This test in general is applicable to NASA payloads (e.g Space Station, STS) See also NASA STD 6001 Test BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) accordingly The 20 igniters selected are tested for the peak flame temperature, burn duration, and peak flame height Each igniter tested develops a flame temperature of (1100 ± 90) °C The igniter flame is sustained for (25 ± 5) s with a peak flame height of (6,5 ± 0,65) cm c Igniters are tested in certified breathing air at standard atmospheric pressure The temperature is measured by a type S thermocouple constructed with a 0,81 mm diameter wire The thermocouple wire is centred geometrically 25,5 mm above the top of the igniter To initiate the igniter, a voltage source capable of providing 15 A (r.m.s.) is connected to a 0,90 mm, bare nickel chromium wire The wire has a nominal resistivity of 2,3 Ω/m and has sufficient length to wrap three, equally spaced turns around the igniter In addition, the leads to the nickel chromium wire coil does not exceed 32 mm to ensure proper ignition of the igniter A calibrated ruler is placed in the test chamber to measure flame height d Before starting the certification, ensure that the thermocouple wires are not touching each other, and that the thermocouple is in proper calibration e To certify a batch of igniters perform the following steps for each of the 20 randomly selected igniters f Place the igniter in the nickel chromium wire coil Pressurize the test chamber to standard atmospheric pressure with certified breathing air Turn on the power to the igniter When ignition is accomplished, turn power off Record the flame temperature (from the thermocouple), the burn time, and the flame height The time from the moment of ignition to the moment of flame extinction (burn time) is obtained using a calibrated stop watch The flame height is determined by measuring the maximum height of the flame above the apex Allow the test chamber to stabilize Before loading the next igniter, clean the wire coil by removing any ash residue with a soft bristled brush The batch of igniters is acceptable for use when no more than one igniter out of the 20 tested fails the specified criteria (see C.9b) Once the batch of igniters is tested and certified, the average peak flame temperature and average burn are calculated, along with the standard deviation C.10 Waste disposal Dispose of any waste generated from manufacturing, cutting or weighing igniters, including an entire batch that fails, per applicable hazardous waste/ environmental regulations 36 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) C.11 Packaging and storing igniters a Package the igniters in a plastic storage container between layers of 3,2 mm thick (minimum) foam corrugated wrap Place the igniters in the grooves of the corrugated wrap The order of placement in the storage container is: corrugated wrap with groove side up; layer of igniters in grooves of corrugated wrap; and corrugated wrap with groove side down Repeat steps C.11a.1 to until the container is full This order of placement put two layers of corrugated wrap between each layer of igniters, and minimizes movement when the box is moved or stored To absorb any excess moisture which can affect the performance of the igniters, place desiccant packets on top of the igniters, inside the container b To prevent the igniters from absorbing moisture during an extended storage period, place the packaged igniters in a desiccator with colour changing desiccant or other type humidity indicator The igniters can be stored for an indefinite period of time, if the desiccant is changed regularly, or the humidity in the desiccator is kept below 18 % 37 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Annex D (informative) Graphical information D.1 Equipment used to determine the oxygen concentration limit Test column Sample holder Threaded shaft ∅ mm 4, Gas burner Diffuser 370 Inox grid mesh mm Spark igniter Insulating ceramic Fuel gas line 10 O2 + N2 mix line 20 10 Figure D-1 Diagram of the equipment used to determine the oxygen concentration limit 38 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) D.2 Frame used to fix the sample ∅25mm 250 mm R≈400mm Arc(5- 8) mm ∅3mm 46mm Clampingdevice: wirediameter 3mm Drawingnot toscale Figure D-2 Frame used to fix the sample 39 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) D.3 Sample holder mm 210 mm A 220 mm A mm mm mm Tube Ø6 mm× mm 46 mm A-A mm R= 23 mm Drawing not to scale Figure D-3 Sample holder 40 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) D.4 Sample holder ∅ 25 mm A Sample on fabric 210 mm (milled 1/2 Ø 6mm) A 200 mm (sample) mm mm mm 40 mm Tube Ø mm × mm A Wire ∅ mm A Sample on fabric Drawing not to scale Figure D-4 Sample holder 41 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) D.5 Samples from thermoplastic polymer materials (10 ± 1) mm (Ø 50 ± 1) mm (2 - 5) mm (2 - 5) mm (200 ± 5) mm (200 ± 5) mm (4 ± 1) mm Glass fibre ∅% mm (2 - 5) mm (2 - 5) mm (2 - 5) mm Drawing not to scale Figure D-5: Samples from thermoplastic polymer materials 42 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) D.6 Test set up for flammability of electric wires under heated wire conditions at 25 % by volume oxygen (V1) Modification as per ISO 6941: 1984 15 16 11 10 90º 75°° Seal 13 (V2) Filter 14 12 Figure D-6: Test set up for flammability of electric wires under heated wire conditions at 25 % by volume oxygen Table D-1: Description of test equipment as per Figure D-6 Item no Description Test chamber Remarks DIN 50050 part 1, modified as per Figure D-5 Volume of chamber = 250 l Upper adapter • To open/close outlet of item • Equipped with two outlets: - for sampling of gases - for measurement of oxygen measurement Shutoff valve V1 To open/close the line for oxygen measurement Distribution unit For distribution of test atmosphere 43 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Item no Description Remarks Shutoff valve V2 To open/close the atmosphere inlet Burner supply inlet Fuel gas/air supply for burner Feedthrough For electrical current load of test sample Sample and burner assembly 60° test Burner 90° relative to wire 30° relative to vertical plane of specimen Burner Bunsen/Tirrill burner type as Figure D-7 Length of flame: 75 mm Length of cone: 25 mm Temperature: (1100 ± 100) °C Measured: 35 mm above burner External gas/air: fuel gas/air 10 Igniter Electrical, of the continuous spark type 11 Support structure Used for example: • sample holder • burner • igniter • electrical connectors Design as Figure D-8 The support structure does not influence the test atmosphere distribution 12 Test atmosphere supply Gas mixture of nitrogen and oxygen ((25 ± 0,2) % volume fraction of oxygen) at ambient conditions Option 1: supply of premixed gases Option 2: unit for mixing gases from separate bottles and measuring oxygen concentration (see item 14) 13 Flowmeter Capable of measuring l/min to 25 l/min 14 Oxygen measuring unit (Optional) 15 Electrical power source Capable of providing a large steady DC current (e.g 0-100 A) sufficient to raise the conductor temperature to the desired level 16 Measurement of wire temperature Instrument to measure: • conductor resistance (4terminal DC resistance bridge measuring mΩ to an accuracy of 0,01 mΩ • voltage accurate to mV • current to an accuracy of 10mA 44 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) General arrangement of modified burner and flame dimensions Temperature measured at 35 mm (approx 150 ºC) 25 mm 75 mm D.7 ∅ 3,3 mm Controlled air supply ∅ 3,3 mm Fuel gas supply Figure D-7 General arrangement of modified burner and flame dimensions 45 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) D.8 General arrangement of apparatus for flammability test Pully support bracket (low thermal conductivity) Upper datum point 600 mm Distance between reference marks Weights as required Flame application point (flame centre datum) 200 mm 75º Bunsen burner support (low thermal conductivity) Bottom clamp support (low thermal conductivity) 30º Figure D-8 General arrangement of apparatus for flammability test 46 BS EN 16602-70-21:2014 EN 16602-70-21:2014 (E) Bibliography EN reference Reference in text Title EN 16601-00 ECSS-S-ST-00 ECSS system - Description, implementation and general requirements NASA STD 6001 Flammability, Odor and Offgassing compatibility Requirements & Test Procedures for Materials That Support Combustion ZZU.0336.028 Standard test method for the determination of the oxygen concentration limit during the combustion of polymer materials (English translation of original Russian title) ISO/CD 14624-1 Space systems - Test Method for Upward Flammability of Materials 47 This page deliberately left blank This page deliberately left blank NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW British Standards Institution (BSI) BSI is the national body responsible for preparing British Standards and other standards-related publications, information and services BSI is incorporated by Royal Charter British Standards and other standardization products are published by BSI Standards Limited About us Revisions We bring together business, industry, government, consumers, innovators and others to shape their combined experience and expertise into standards -based solutions Our British Standards and other publications are updated by amendment or revision The knowledge embodied in our standards has been carefully assembled in a dependable format and refined through our open consultation process Organizations of all sizes and across all sectors choose standards to help them achieve their goals Information on standards We can provide you with the knowledge that your organization needs to succeed Find out more about British Standards by visiting our website at bsigroup.com/standards or contacting our Customer Services team or Knowledge Centre Buying standards You can buy and download PDF versions of BSI publications, including British and adopted European and international standards, through our website at bsigroup.com/shop, where hard copies can also be purchased If you need international and foreign standards from other Standards Development Organizations, hard copies can be ordered from our Customer Services team Subscriptions Our range of subscription services are designed to make using standards easier for you For further information on our subscription products go to bsigroup.com/subscriptions With British Standards Online (BSOL) you’ll have instant access to over 55,000 British and adopted European and international standards from your desktop It’s available 24/7 and is refreshed daily so you’ll always be up to date You can keep in touch with standards developments and receive substantial discounts on the purchase price of standards, both in single copy and subscription format, by becoming a BSI Subscribing Member PLUS is an updating service exclusive to BSI Subscribing Members You will automatically receive the latest hard copy of your standards when they’re revised or replaced To find out more about becoming a BSI Subscribing Member and the benefits of membership, please visit bsigroup.com/shop With a Multi-User Network Licence (MUNL) you are able to host standards publications on your intranet Licences can cover as few or as many users as you wish With updates supplied as soon as they’re available, you can be sure your documentation is current For further information, email bsmusales@bsigroup.com BSI Group Headquarters 389 Chiswick High Road London W4 4AL UK We continually improve the quality of our products and services to benefit your business If you find an inaccuracy or ambiguity within a British Standard or other BSI publication please inform the Knowledge Centre Copyright All the data, software and documentation set out in all British Standards and other BSI publications are the property of and copyrighted by BSI, or some person or entity that owns copyright in the information used (such as the international standardization bodies) and has formally licensed such information to BSI for commercial publication and use 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 Details and advice can be obtained from the Copyright & Licensing Department Useful Contacts: Customer Services Tel: +44 845 086 9001 Email (orders): orders@bsigroup.com Email (enquiries): cservices@bsigroup.com Subscriptions Tel: +44 845 086 9001 Email: subscriptions@bsigroup.com Knowledge Centre Tel: +44 20 8996 7004 Email: knowledgecentre@bsigroup.com Copyright & Licensing Tel: +44 20 8996 7070 Email: copyright@bsigroup.com