1、CEN ENx702 94 = 3404589 0091970 711 = BRITISH STANDARB Protective clothing - Protection against heat and flame - Test method: Determination of the contact heat transmission through protective clothing or its materials The European Standard EN 702 : 1994 has the status of a British Standard BS EN 702
2、 : 1995 CEN EN*702 94 m 3404589 0093973 658 m BS EN 702 : 1995 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee PSM/35, Clothing for protection against heat and flame, upon which the following bodies were represented: Amal
3、gamated Engineering Union British Clothing Industry Association British Foundry Association British Leather Confederation British Railways Board British Steel plc British Textile Confederation British Extile Technology Group Chemical Industries Association Chief and Assistant Chief Fire Officers Ass
4、ociation Confederation of British Wool Textiles Limited Health and Safety Executive Home Office Industrial Safety (Protective Equipment) Manfacturers Association Institute of Occupational Hygienists Institute of Purchasing and Supply Institution of Fire Engineers International Wool Secretariat Lambe
5、g Industrial Research Association Medical Research Council Ministry of Defence Society of British Gas Industries Trades Union Congress This British Standard, having been prepared under the direction of the Health and Environment Sector Board, was published under the authority of the Standards Board
6、and comes into effect on 15 May 1995 O BSI 1995 The following ES1 references relate to the work on this standard: Committee reference PSM/35 Draft for comment 92/39066 DC ISBN O 580 23995 O Amendments issued since publication Amd. No* I Date I Text affected BS EN 702 : 1995 National foreword This Br
7、itish Standard has been prepared by Technical Committee PSM/35 and is the English language version of EN 702 : 1994 Protective clothing - Protection against heat andjlame - l in each case the operation shall be carried out at a constant speed. By monitoring the temperature of the calorimeter, the th
8、reshold time is determined. 4 Apparatus 4.1 Heating cylinder The heating cylinder is constructed from a suitable metal which can withstand temperatures up to over 500 OC (e.g. pure nickel). Fgure 1 shows a possible version of the heating cylinder. The contact surface shall have a diameter of (25,2 f
9、 0,05) mm and shall be surface ground. A central boring ends 3 mm above the lower surface of the heating cylinder. This boring is intended to hold the temperature sensor, necessary for the temperature regulation of the heating cylinder, and its diameter should be chosen accordingly. A spiral slot of
10、 depth D, width B and pitch 2 is machined in the upper part of the heating cylinder. D, B and 2 shall be chosen in such a way that the total heated length of a heating conductor can be placed in the slot. The heating cylinder shall be enclosed by a heat resistant insulation, leaving free the bottom
11、contact surface. 4.2 Calorimeter The calorimeter as shown in figure 2 consists of a cylindrical disc of black anodized pure aluminium of (25 f 0,05) mm diameter and (5 IC 0,OZ) mm thickness which is fixed on a mounting made from polyamide 6.6. The upper contact surface of the calorimeter shall be su
12、rface ground before anodization and on the lower surface a temperature sensor (e.g. platinum resistor) shall be fixed. 4.3 Assembly Figure 3 shows a possible version of the assembly. The heating cylinder and calorimeter are mounted with parallel faces and with their symmetrical axes in line in a sup
13、porting frame. Provision shall be made for a controlled speed movement of either the heating cylinder down towards the calorimeter or the calorimeter up towards the heating cylinder. The additional weight shall be dimensioned in such a way that the contact force is (49 f 0,s) N. Between measurements
14、, during cooling periods, a suitable shielding shall be put between the heating cylinder and calorimeter in order to prevent the calorimeter from being heated up by the thermal radiation of the heating cylinder. 4.4 Electronics Suitable electronic devices shall be provided to: - heat up the heating
15、cylinder to at least 500 OC and control the temperature; - control the contacting speed; - measure and register the calorimeter temperature to an accuracy of k 0,l OC; - measure the threshold time. CEN EN*702 94 3404587 OOLib L3T Page 4 EN 702 : 1994 5 Sampling and conditioning 5.1 Sampling At least
16、 three circular specimens of 80 mm diameter shall be taken for each contact temperature from the product or from a piece of the material intended for the manufacture of the product. 5.2 Conditioning Before the test the specimens shall be conditioned for at least 24 h in an atmosphere of (20 f 2) OC
17、and (65 f 5) % relative humidity. 6 Test method 6.1 Starting conditions The measurements shall be carried out in an atmosphere having a temperature of (20 f 5) OC and a relative humidity between 15 % and 80 %. The heating cylinder shall be brought to the selected contact temperature f 2 % (in OC). T
18、he temperature of the calorimeter shall be at room temperature f 2 OC before the start of each test. The test shall be started not later than 3 min after the specimen has been taken out of the conditioning atmosphere according to 5.2. 6.2 Procedure Place the specimen on the calorimeter so that its o
19、uter face looks upward. Remove the shielding between the heated cylinder and the calorimeter and bring the heated cylinder into contact with the calorimeter with a contacting speed of (5,O f 0,2) mm/s. Measure and record the temperature of the calorimeter during the test. Carry out at least three me
20、asurements at each contact temperature. 6.3 Evaluation Determine the threshold time i$ to the nearest 0,l c. 7 Test report The test report shall contain the following particulars: a) reference to this European Standard; b) name of supplier of product or material; c) name, as given by the supplier, a
21、nd description of the product or the material; d) contact temperature(s) T,; e) threshold time i$: individual values or, if five or more measurements per contact temperature have been made, mean value and standard deviation; f) description of observed changes of the specimens; g) date of testing; h)
22、 any deviation from this standard. 940 $24,8 t- III I II III m l Dimensions in miiiimetres Key 1 Slot for heating conductor 2 Boring for temperature sensor 3 Contact surface *) Diameter of the boring appropriate for the temperature sensor Figure 1. Heating cylinder CEN EN8702 94 3404589 0093977 O76
23、= Page 5 EN 702 : 1994 940 Dimensions in millimetres Key 1 Cylindrical disc, made from pure aluminium, black anodized 2 Temperature sensor, e.g. platinum resistor 3 Mounting, made from polyamide 6.6 *) Maximum depth of thread holes for the mounting of the calorimeter Figure 2. Calorimeter Key 1 Addi
24、tional weight 2 Heated cylinder with insulation 3 Shielding 4 Calorimeter contact surface 5 Supporting frame 6 Motor Figure 3. Assembly BS EN 702 : 1995 BSI 389 Chiswick High Road London W4 4AL 9505- 5- 0.4k- RTL BSI - British Standards Institution BSI is the independent national body responsible fo
25、r preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Contract requirements A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsib
26、le for their correct application. Revisions British Standards are updated by amendment or revision. Users of British Standards should make sure that they possess the latest amendments or editions. Any person who finds an inaccuracy or ambiguity while using this British Standard should bring it to th
27、e attention of the QuaIity Manager, BSI without delay so that the matter may be investigated swiftly. 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, internationa
28、l and foreign standards publications should be addressed to Customer Services, Sales Department at Chiswick: Tel: 0181 996 7000; Fax: 0181 996 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 Stand
29、ards, unless otherwise requested. Information on standards BSI provides a wide range of information on national, European and international standards through its Library, the Standardline Database, the BSI Information Technology Service (BITS) and its lchnical Help to Exporters Service. Contact the
30、Information Department at Chiswick: Tel: O181 996 7111; Fax: 0181 996 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 Customer Services, Membership a
31、t Chiswick: Tel: 0181 996 7002; Fax: 0181 996 7001. Copyright Copyright subsists in all BSI publications and no part may be reproduced in any form without the prior permission in writing of BSI. This does not preclude the free use, in the course of implementing the standard of necessary details such
32、 as symbols and size, type or grade designations including use by incorporation into computer programs, but where these details are reproduced including without limitation in printed form, in computer programs or in any other form whatsoever, the permission in writing of BSI must be obtained and if granted will be on terms including royalty, before the product is sold, licensed or otherwise exploited for commercial gain. Enquiries about copyright should be made to the Copyright Manager at Chiswick. ISBN O 580 23995 O PSM/35
