1、ASD STANDARD NORME ASD ASD NORM prEN 3475-602 Edition P 2 September 2006 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATION Gulledelle 94 - B-1200 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 763 3565 - www.asd-stan.org ICS: 49.060 Supersedes edition P 1 of No
2、vember 2001 Descriptors: Aerospace industry, aircraft equipment, electrical cable test ENGLISH VERSION Aerospace series Cables, electrical, aircraft use Test methods Part 602: Toxicity Srie arospatiale Cbles lectriques usage aronautique Mthodes dessais Partie 602 : Toxicit Luft- und Raumfahrt Elektr
3、ische Leitungen fr Luftfahrtverwendung Prfverfahren Teil 602: Giftigkeit This “Aerospace Series“ Prestandard has been drawn up under the responsibility of ASD-STAN (The AeroSpace and Defence Industries Association of Europe - Standardization). It is published for the needs of the European Aerospace
4、Industry. It has been technically approved by the experts of the concerned Domain following member comments. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identifi
5、cation of the standard. After examination and review by users and formal agreement of ASD-STAN, it will be submitted as a draft European Standard (prEN) to CEN (European Committee for Standardization) for formal vote and transformation to full European Standard (EN). The CEN national members have th
6、en to implement the EN at national level by giving the EN the status of a national standard and by withdrawing any national standards conflicting with the EN. Edition approved for publication 30 September 2006 Comments should be sent within six months after the date of publication to ASD-STAN Electr
7、ical Domain Copyright 2006 by ASD-STAN Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-602:20062 Contents Page Foreword . 2 1 Scope 3 2 Norm
8、ative references 3 3 Terms and definitions. 3 4 Principle of method. 4 5 Preparation for analysis . 4 5.1 General . 4 5.2 Probes for gas sampling 5 5.3 Gas sampling system for non-reactive gases 5 5.4 Gas sampling for reactive Gases 6 5.5 Checking of sampling systems . 7 6 Analytical chemistry . 8 6
9、.1 Colorimetric method of measurement 8 6.2 Potentiometric method of measurement (Wet Analysis) for determination of the halogenides F, Cl. 8 7 Requirements 10 8 Report. 10 Foreword This standard was reviewed by the Domain Technical Coordinator of ASD-STANs Electrical Domain. After inquiries and vot
10、es carried out in accordance with the rules of ASD-STAN defined in ASD-STANs General Process Manual, this standard has received approval for Publication. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction o
11、r networking permitted without license from IHS-,-,-prEN 3475-602:2006 3 1 Scope This test method is intended for use in determining the concentration of specific gas components of smoke released by cable insulation materials. This test method should be used to measure and describe the properties of
12、 cable insulation materials in response to heat and flame under controlled laboratory conditions. This standard should be used to measure and describe the properties of products in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fi
13、re hazard or fire risk of materials, products, or assemblies under actual fire conditions. However results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use. 2 Nor
14、mative 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. EN 3475-601, Aerospace series C
15、ables, electrical, aircraft use Test methods Part 601: Smoke density. 1) 3 Terms and definitions For the purposes of this standard, the following terms and definitions apply. 3.1 ppm parts per million, concentration 3.2 colorimetry analytical procedure using colour comparison 3.3 potentiometry deter
16、mination of ionic concentration by electrochemical measurements 3.4 in situ at the site (in this case: in the NBS chamber) 3.5 halogenides the group of chlorides, fluorides, bromides and iodides They have a strong electrophilic character and are therefore very reactive. 1) Published as ASD Prestanda
17、rd at the date of publication of this standard. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-602:20064 3.6 absorbent liquid suitable for
18、collecting gas components 3.7 impinger bottle special glass vessel for the absorption solution 3.8 test tube glass tube filled with a special reagent for quantitative identification of a specific gas component 3.9 molarity concentration of a solution expressed as mol (gr/molecular weight) of solute
19、per litre of solution 3.10 ISA lonic Strength Adjuster 3.11 NTP Normal Temperature and Pressure 3.12 NBS National Bureau of Standards, Washington 4 Principle of method The smoke gas produced under the conditions of the smoke density test described in EN 3475-601 is subjected to an analysis depending
20、 on the gas components to be investigated. The concentration of non-reactive gas components is determined by means of the colorimetric procedure. In this case, test tubes filled with a solid reagent are used; if a specific gas component exists, the indicating layer discolours due to chemical reactio
21、ns. The length of the colour change is a measure for the concentration. The concentration of the reactive gases is determined by potentiometry; in this case, electrochemical potentials which can be converted into ppm concentrations after plotting of a calibration curve are measured with ion-specific
22、 electrodes in connection with a special reference electrode. 5 Preparation for analysis 5.1 General The specimens arranged vertically in a closed test chamber, are chemically decomposed according to EN 3475-601 by thermal radiation alone or in combination with flaming. The resulting smoke portions
23、are optically measured according to this test method. In this connection, a gas sample is taken at a time, which has to specified in a test plan. The decomposition gases resulting from thermal degradation are determined qualitatively and quantitatively by means of the analytical procedure described
24、herein. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-602:2006 5 5.2 Probes for gas sampling The gases are sampled by means of three probe
25、s (internal diameter 6-8 mm) extending into the geometric center of the chamber. Resistant probe materials (such as polypropylene or PTFE) are to be selected due to the reactive behaviour of the halogenides. The probes are to be connected gastight to the tube fittings for gas sampling at the upper s
26、ide of the test chamber. Connections not used are to be sealed. One of the probes inserted into the chamber is to be provided with a rubber sleeve for attachment of the test tube for colorimetric “in situ“ measurement. 5.3 Gas sampling system for non-reactive gases 5.3.1 General Figures 1 and 2 show
27、 the basic set-ups for allowable gas sampling systems. 5.3.2 Pipe system for the gas bag A pipe system with a maximum length of 3 m is to be installed between the gas sampling point at the chamber and the place of gas collection. If the gas pipe system cannot be heated, thermal insulation of the pip
28、es is to be provided so as to avoid the formation of condensates. The pipes must have an inner width of 6 mm to 8 mm. Plastic hoses or pipes must be used and, depending on the suitability, polyethylene; butadiene or silicone rubber types can also be used. PTFE and are recommended for special require
29、ments with regard to corrosion resistance with temperature load. The gas pipe end facing the chamber is to be provided with a stopcock. 5.3.3 Collection of gases Foil bags with a capacity of 10 l to 15 l and a high mechanical and chemical resistance are to be used for the collection of the non-react
30、ive gas components to be analyzed. Polyvinylidene fluoride with low gaseous diffusion and water vapour permeability is recommended as foil material so that a change in the gas composition due to diffusion processes is negligible: Permeability of gas for O2 max. 20 cm3 NTP/m2 per 24 h N2 max. 6 cm3 N
31、TP/m2 per 24 h CO2 max. 140 cm3 NTP/m2 per 24 h Water vapour max. 13 g/m2 per 24 h Furthermore, the bags used must be provided with a stopcock. 5.3.4 Gas collection Two approved gas collection processes are available, collection by means of vacuum or by suction pump. Vacuum method: A vacuum tank wit
32、h a minimum capacity of 15 l is recommended for collecting the gas components to be analyzed in the above-stated foil bag. The design of the tank should be 5 l greater then the volume of the bag. The evacuation pressure is to be monitored by a vacuum gauge. The vacuum tank is to be provided with a v
33、entilation valve and a connection for the vacuum pump. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-602:20066 The tank cover of 10 mm thi
34、ck acrylic glass minimum is provided with a hole into which a quick-release coupling is to be installed gastight in order to connect the gas bag, on the one side, with the gas pipe, on the other side. A vacuum pump producing a vacuum in the tank capable of filling a gas bag according to within 20 s
35、is to be used. Procedure: The shut-off valve at the chamber is to be closed. The gas bag is to be connected to the gas sampling system via the quick-release coupling while ensuring that the shut-off valve at the gas bag is open. The tank is to be sealed with a cover. The vacuum pump is to be switche
36、d on and the following components are to be evacuated: gas pipe gas bag vacuum tank At the time of sampling, the stopcock at the test chamber (1) and the stopcock at the vacuum tank (2) are opened. The other shut-off valves are still closed. After filling of the gas bag, both stopcocks (1) and (2) i
37、n the supply line are to be closed. Then the vacuum tank is vented via the ventilation valve (5) and the pump is switched off. The stopcock at the bag is closed and the filled bag is disconnected from the quick-release coupling and to be immediately analyzed. Suction pump method: The following proce
38、dure can also be used as an alternative to the vacuum method for filling the foil bag. The set-up of the equipment up to the suction pump is in accordance with 5.3.2. A manifold is to be installed at the inlet and outlet of the pump as shown in Figure 2. The manifold is used to vent the gas bag and
39、to flush the gas pipe. The suction pump capable of filling a gas bag according to within 20 s is to be used. Procedure: The shut-off valve (1) at the chamber is to be closed. The gas bag is to be connected to the coupling (8) in front of the pump manifold. The shut-off valves (2) and (4) are to be o
40、pened. The shut-off valve at the gas bag is to be opened. The suction pump is to be switched on and the gas bag is to be evacuated. The shut-off valve at the gas bag and the shut-off valve (2) are to be closed and the pump is to be switched off. The shut-off valve (3) is opened and the shut-off valv
41、e (4) is closed. The closed gas bag is to be connected to the coupling (6) at the pump outlet and the shut-off valve at the gas bag is to be opened. At the time of sampling, the shut-off valve (1) at the test chamber is opened. The suction pump is to be switched on. After 30 s at the earliest, the s
42、hut-off valve (3) is closed and the shut-off valve (4) in front of the gas bag is opened. After filling the gas bag, the shut-off valve (4), the gas bag valve and the chamber shut-off valve (1) are all to be closed. The suction pump is to be switched off. The filled bag is disconnected from the suct
43、ion pump and the contents immediately analyzed. 5.4 Gas sampling for reactive Gases 5.4.1 “In situ” measurements for colorimetric determination of Hydrogenchloride (HCI) and Hydrogenfluoride (HF) The samples for measuring the hydrogen fluoride and chloride with colorimetric test tubes are taken dire
44、ctly from test chamber by means of a suction pump. The suction capacity of the pump under load must comply with the values specified by the manufacturer of the test tubes. A gas pipe of the material and diameter recommended in 5.3.2 connects the probe to the suction pump. A shut-off valve is to be i
45、nstalled in front of the suction pump as well as a volumetric flowmeter for flow control. The basic set-up is shown in Figure 3. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted wi
46、thout license from IHS-,-,-prEN 3475-602:2006 7 Procedure: Prior to the commencement of the test, both tips of the test tube are broken off with a tube opener and inserted into the probe with the arrow pointing towards the pump. The volumetric suction flow at the suction pump is selected and checked
47、 as specified by the manufacturer for the test tube. A certain quantity of the gas sample to be tested, which was specified by the manufacturer, is now sucked through the test tube at the set volumetric suction flow. The existence of the specific gas results in instantaneous discoloration. Observe f
48、or cross- sensitivities which are explained in the relevant directions for use. 5.4.2 “In situ” measurement for potentiometric determination of Hydrogenfluoride (HF) and Hydrogenbromide (HBr) and Hydrogenchlorine(HCI) The equipment set-up must comply with Figure 3. The samples for measuring the halo
49、genides by means of an absorption solution are taken directly from the test chamber by means of a suction pump. The suction capacity of the pump should not exceed 2 000 cm3/min. A gas pipe of the material and diameter recommended in 5.3.2 connects the probe to the suction pump. A shut-off valve is to be installed at the side facing the chamber. A washing bottle for cleaning the gases, a dosagi
