1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 2825:2011Aerospace series Burningbehaviour of non metallicmaterials under the influenceof radiating heat and flames Determination of smokedensityBS EN 2825:2011 BRITISH STA
2、NDARDNational forewordThis British Standard is the UK implementation of EN 2825:2011.The UK participation in its preparation was entrusted to TechnicalCommittee ACE/65, Non-metallic materials for aerospace purposes(excluding textiles).A list of organizations represented on this committee can beobtai
3、ned on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 72914 0ICS 13.220.40; 49.025.99Compliance with a British Standard cannot confer immunity fromlegal obligati
4、ons.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 May 2011.Amendments issued since publicationDate Text affectedBS EN 2825:2011EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 2825 April 2011 ICS 13.220.40; 49.025.99 English Version A
5、erospace series - Burning behaviour of non metallic materials under the influence of radiating heat and flames - Determination of smoke density Srie arospatiale - Comportement au feu des matriaux non mtalliques sous laction de chaleur rayonnante et de flammes - Dtermination de la densit de fume Luft
6、- und Raumfahrt - Brandverhalten nichtmetallischer Werkstoffe unter Einwirkung von strahlender Wrme und Flammen - Bestimmung der Rauchdichte This European Standard was approved by CEN on 17 December 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the c
7、onditions 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 member. This European Standard ex
8、ists 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 CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national s
9、tandards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland a
10、nd United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 2825:
11、2011: EBS EN 2825:2011EN 2825:2011 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Short description of the test method .4 4 Terms and definitions .4 5 Designation 5 6 Test equipment 5 7 Specimens 5 7.1 Number of specimens .5 7.2 Conditioning .5 7.3 Dimensions and shape of specim
12、ens .5 7.4 Specimen mounting.5 8 Procedure .5 9 Calculation of test results .7 10 Test report 7 Annex A (normative) Example for a test report on the determination of smoke density 8 BS EN 2825:2011EN 2825:2011 (E) 3 Foreword This document (EN 2825:2011) has been prepared by the Aerospace and Defence
13、 Industries Association of Europe - Standardization (ASD-STAN). After enquiries and votes carried out in accordance with the rules of this Association, this Standard has received the approval of the National Associations and the Official Services of the member countries of ASD, prior to its presenta
14、tion to CEN. 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 October 2011, and conflicting national standards shall be withdrawn at the latest by October 2011. Attention is drawn to the possibilit
15、y 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. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bou
16、nd to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
17、Sweden, Switzerland and the United Kingdom. BS EN 2825:2011EN 2825:2011 (E) 4 1 Scope This European Standard defines a test method for determination of the smoke density due to pyrolitic decomposition of solid materials and composite materials of up to 25 mm in thickness under the influence of radia
18、nt heat only or with simultaneous flame application. The test results enable a comparison of the smoke production of different materials or material configurations under the conditions specified in this standard. NOTE 1 The smoke gas density is determined according to the specific environmental and
19、test conditions defined in EN 2824 and this standard. No studies have been made up to now to determine whether the results can be transferred to differing conditions, particularly to actual fire conditions. NOTE 2 The burning behaviour - and consequently the smoke density - of aerospace materials ar
20、e not only influenced by the type of material but also to a large extent by the configuration, the specific surface and mass, the combination with other materials, the means of joining as well as the processing technique. 2 Normative references The following referenced documents are indispensable fo
21、r 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. EN 2824, Aerospace series Burning behaviour of non metallic materials under the influence of radiating h
22、eat and flames Determination of smoke density and gas components in the smoke of materials Test equipment apparatus and media 1)EN ISO 13943:2008, Fire safety Vocabulary 3 Short description of the test method The specimens are vertically arranged in a closed test chamber according to EN 2824 and sub
23、jected to decomposition by radiant heat only or with flame application. The smoke density is measured by means of the reduction of light transmission as smoke accumulates and expressed in terms of specific optical density which is derived from a geometric factor and the measured light obscuration. 4
24、 Terms and definitions For the purposes of this document, the terms and definitions given in EN ISO 13943 apply. 1) Published as ASD-STAN Prestandard at the date of publication of this standard by Aerospace and Defence Industries Association of Europe-Standardization (ASD-STAN), (www.asd-stan.org).
25、BS EN 2825:2011EN 2825:2011 (E) 5 5 Designation EXAMPLE Description block TEST Identity block EN2825A Number of this standard Code letter of test method (see below) A = indicates that the method is used to test a material in the Flaming mode only. B = indicates that the method is used to test a mate
26、rial in both the Flaming mode and the Norm-Flaming mode. 6 Test equipment Testing shall be carried out in a test chamber according to EN 2824. 7 Specimens 7.1 Number of specimens According to EN 2824. 7.2 Conditioning According to EN 2824. 7.3 Dimensions and shape of specimens According to EN 2824.
27、7.4 Specimen mounting According to EN 2824. 8 Procedure 8.1 When performing the test, precautions shall be taken to remove potentially hazardous gases from the area of operation. 8.2 During the warm-up period, all electric systems (furnace, light source, photometer-readout) shall be switched on, the
28、 exhaust vent and chamber door shall be closed and the inlet vent be open. When the temperature on the centre surface of the back wall has reached a steady-state value of (35 2) C, the chamber is ready for calibrating or testing. To increase the chamber wall surface temperature to the stated level,
29、an auxiliary heater may be used, but shall be removed prior to performing tests. Conversely, to decrease this temperature, the exhaust blower may be used to introduce cooler air. The furnace shall be calibrated at periodic intervals. BS EN 2825:2011EN 2825:2011 (E) 6 8.3 A specimen holder with inser
30、ted calcium silicate sheet shall always be located directly in front of the furnace, except when it is replaced by the specimen holder during a test or the radiometer during calibration. It shall be returned immediately to this position when testing or calibration is completed to prevent excessive h
31、eating of the opposite wall surface. 8.4 During the daily calibration, the radiometer shall be placed on the horizontal rods of the furnace support framework and accurately positioned in front of the furnace opening by displacing the “blank“ specimen holder against the prepositioned stop. With the c
32、hamber door closed and the inlet vent opened, the compressed air supply to the radiometer cooler shall be adjusted to maintain the radiometer body temperature at (93 3) C. After the system has reached steady-state the furnace transformer shall be adjusted to obtain - as per radiometer calibrating cu
33、rve - an output signal corresponding to an irradiance of (25,0 0,5) kW/m2averaged over the radiometer receiver area. After the prescribed irradiance level has reached steady-state, the radiometer shall be removed from the chamber and replaced by the “blank“ specimen holder. A suitable voltmeter or r
34、ecorder shall indicate the radiometer signal. The calibration of the radiometer has to be checked regulary because the characteristics may change by use. The whole system has to be verified finally by testing standardized samples or by comparative testing. 8.5 After the system has reached steady-sta
35、te (end of warm-up period), the amplifier sensitivity shall be adjusted to obtain a 100 % transmittance indication in the least sensitive measuring range with free light path. The “dark current“ reading shall be set to zero by compensating the dark current with the light beam blocked in the most sen
36、sitive measuring range of the photometer to 0 % transmittance. Prior to commencing the test the zero line of the recorder shall be adjusted accordingly. 8.6 For non-flaming exposures the burner shall be removed. For flaming exposures the burner shall be positioned in front of the lower edge of the s
37、pecimen, as described in 8.3 and Figure 8 of EN 2824. The burner distances relative to the blank specimen holders shall be checked prior to testing. 8.7 Before accurately positioning the specimen in front of the furnace, the chamber shall be flushed for about 2 min with the door and exhaust and inle
38、t vents open. The wall temperature, measured with the back wall thermocouple according to EN 2824, shall be verified when starting the test (see 8.2). 8.8 The exhaust vent and blower shall be closed. The loaded specimen holder shall be placed on the bar support and pushed into position in front of t
39、he furnace by displacing the blank holder to the stop. The chamber door shall be closed quickly, starting simultaneously the recorder or plotter. The inlet vent shall only be completely closed when the photometer indicates the presence of smoke. 8.9 The light transmittance and the corresponding time
40、 shall recorded as a continuous plot. The necessary full-scale range changes shall be made and noted in decade steps. The percentage error of a reading becomes progressively worse at the lower portion of the scale. Avoid light transmittance measurement on scale readings less than 10 by making the ap
41、propriate decade range change. 8.10 The increase in chamber pressure shall be observed using the manometer described in EN 2824. If negative pressure develops after very intense burning of specimen, the inlet vent shall be slightly opened for pressure equalization. During the test, the gas flow of t
42、he burner shall be kept constant. 8.11 Unless otherwise specified, the test duration shall be 6 min. 8.12 If transmittance falls below 0,01 %, the chamber window shall be covered with an opaque screen to avoid possible light-scattering effects from room light. The ND-2 filter in the photometric syst
43、em according to EN 2824, Figure 5, shall be removed from the light path to extend the measuring range. The filter shall be replaced before exhausting smoke from the chamber. BS EN 2825:2011EN 2825:2011 (E) 7 8.13 Within 1 min after termination of the test, the specimen shall be displaced from the fr
44、ont of the furnace by pushing the blank specimen holder with the positioning rod and exhausting of the chamber be started. Continue to exhaust with the inlet vent open until maximum transmittance is reached. This transmittance value shall be recorded. 9 Calculation of test results The specific optic
45、al density Dsshall be calculated to the following formula: Ds= G . log10. t100Twhere Ds is the specific optical density; Ttis the percent light transmission at the time, in minutes; G is a geometric factor (see below). G = L AV.here G = cm 91,4) 6,5 (6,5cm 61) 91,4 (91,4= 132 where Vis the chamber v
46、olume in cubic centimetres; A is the exposed specimen surface area, in square centimetres; L is the light path length, in centimetres. The arithmetic mean for the smoke density Dsshall be calculated in each case from the individual values measured. For very high Dsvalues the ND-2 filter shall be rem
47、oved and then a correction factor shall be added to the calculation. 10 Test report The test report (see Annex A) shall include the following: 10.1 Complete description of the specimen material and the specimen construction (material designation, manufacturers identification, manufacturer/supplier,
48、manufacturing batch number, order number, construction, specimen thickness, density etc.). 10.2 Period and conditions of specimen conditioning. 10.3 Test conditions (with or without flame application). 10.4 Number of tests performed. 10.5 Tabulation of individual results after 1 min, 1,5 min and 2 m
49、in and in 1 min intervals (up to 6 min). 10.6 Observations concerning smoke generation, such as colour of the smoke, nature of soot deposits etc. 10.7 Date of testing. 10.8 Signature. BS EN 2825:2011EN 2825:2011 (E) 8 Annex A (normative) Example for a test report on the determination of smoke density Material . Material standard Technical specification Semi-finished product standard Trade-mark of the product Name and address of manufacturer . Name and address of supplier . Purchaser . Order No. Delivery bill No. Date of manufacture Manufact
