BS EN 2591-306-1998 Elements of electrical and optical connection - Test methods - Mould growth《电气和光学连接元件 试验方法 长霉》.pdf

1、BRITISH STANDARD AEROSPACE SERIES BS EN 2591-306:1998 Elements of electrical and optical connection Test methods Part 306: Mould growth The European Standard EN 2591-306:1998 has the status of a British Standard ICS 49.060BSEN2591-306:1998 This British Standard, having been prepared under the direct

2、ionof the Engineering SectorBoard, was published underthe authority of the Standards Board and comes intoeffect on 15 August 1998 BSI 04-1999 ISBN 0 580 30300 4 National foreword This British Standard is the English language version of EN2591-306:1998. The UK participation in its preparation was ent

3、rusted by Technical Committee ACE/6, Aerospace avionic, electrical and fibre optic technology, to Subcommittee ACE/6/3, Aerospace Connectors, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interp

4、retation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards w

5、hich implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does

6、 not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an insid

7、e front cover, pages i and ii, theEN title page, pages 2 to 6 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date Com

8、mentsBSEN2591-306:1998 BSI 04-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of EN 2591-306 3ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 2591-306 June 1998 ICS 49.060 Descriptors: Aircraft industry, aircraft equipment, connecting equipment, test English ve

9、rsion Aerospace series Elements of electrical and optical connection Test methods Part 306: Mould growth Srie arospatiale Organes de connexion lectrique et optique Mthodes dessais Partie 306: Moisissures Luft- und Raumfahrt Elektrische und optische Verbindungselemente Prfverfahren Teil 306: Schimmel

10、wachstum This European Standard was approved by CEN on 22 June1997. CEN 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 bibliographica

11、l references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN 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 me

12、mber into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Port

13、ugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide f

14、or CEN national Members. Ref. No. EN 2591-306:1998 EEN2591-306:1998 BSI 04-1999 2 Foreword This European Standard has been prepared by the European Association of Aerospace Manufacturers (AECMA). After inquiries and votes carried out in accordance with the rules of this Association, this Standard ha

15、s received the approval of the National Associations and the Official Services of the member countries of AECMA, prior to its presentation 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 D

16、ecember 1998, and conflicting national standards shall be withdrawn at the latest by December 1998. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denma

17、rk, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Preparation of specimens 3 4 Test preparation 3 5 Method 4 Table 1 Cultures 3EN25

18、91-306:1998 BSI 04-1999 3 1 Scope This standard specifies a method of assessing the ability of elements of connection or of samples of their component materials to withstand mould growth. It shall be used together with EN2591. 2 Normative references This European Standard incorporates by dated or un

19、dated reference provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when

20、 incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 2591, Aerospace series Elements of electrical and optical connection Test methods General. EN 2591-101, Aerospace series Elements of electrical and optical connection Te

21、st methods Part 101: Visual examination. EN 2591-206, Aerospace series Elements of electrical and optical connection Test methods Part 206: Measurement of insulation resistance. EN 2591-207, Aerospace series Elements of electrical and optical connection Test methods Part 207: Voltage proof test. 3 P

22、reparation of specimens 3.1 Material samples They shall be cleaned with products which shall not interfere with the subsequent growth of mould and shall be submitted to test method A. 3.2 Elements of connection They shall be prepared as specified, shall not receive any preliminary cleaning treatment

23、 and shall be submitted to test method B. 3.3 Unless specified in the technical specification, the following details shall be stated: type of sampling; method to be used (A or B); period of exposure; extent of acceptable mould growth; preliminary cleaning (if applicable); initial measurements (if ap

24、plicable); final measurements and requirements (if applicable). 4 Test preparation 4.1 Mould cultures The following cultures (Table 1) shall be used to carry out the test. The nature of the attack to be expected from each culture is indicated, but all strains shall be used together, whatever the nat

25、ure of the specimen. Table 1 Cultures Number Name Strain Typical culture (for guidance only) Nature 1 Aspergillus niger V.Tieghem ATCC.6275 Grows profusely on many materials and is resistant to copper salts 2 Aspergillus terreus Thom. PQMD.82j Attacks plastic materials 3 Aureobasidium pullulans (De

26、Barry) Arnaud ATCC.9348 Attacks paints and varnishes 4 Paecilomyces varioti Bainier IAM.5001 Attacks plastics and leather 5 Penicillium funiculosum Thom. IAM.7013 Attacks many materials especially textiles 6 Penicillium ochro-chloron Biourge ATCC.9112 Resistant to copper salts and attacks plastics a

27、nd textiles 7 Scopulariopsis brevicaulis (Sacc.) Bain Var. Glabra Thom IAM.5146 Attacks rubber 8 Trichoderma viride Pers. ex Fr. IAM. 5061 Attacks cellulose textiles and plasticsEN2591-306:1998 4 BSI 04-1999 Cultures shall be obtained from an approved mycological institute which shall certify that t

28、hey are suitable for the test. 4.1.1 The cultures shall be supplied as spores, on an agar medium, in glass containers with cotton plugs, or as otherwise considered appropriate by the mycological institute. 4.1.2 The cultures shall be stored in a refrigerator at a temperature between 5 C and 10 C. Th

29、e cultures used for preparing the test suspension shall be preferably between 14 d and 21 d old. In no case shall cultures which are less than 14 d or more than 28 d old be used. The stoppers shall not be removed until the suspension is about to be made, and only one suspension shall be made from th

30、e opened container. A fresh, unopened container shall be used for each preparation of a suspension. 4.2 Preparation of spore suspension 4.2.1 The suspension shall be prepared in deionized water to which has been added 0,05 % of a non-fungicidal wetting agent. An agent based on N-methyl or on dioctyl

31、 sodium sulphosuccinate may be accepted. 4.2.2 10 ml of the water with wetting agent shall be poured gently into each tube. A platinum or a nichrome wire shall be sterilized by heating to red heat in a flame and allowed to cool. This wire shall then be used to scrape gently the surface of the cultur

32、e to liberate spores. The liquid shall be slightly agitated to disperse the spores without detaching mycelial fragments. The suspension shall then be decanted into a flask. 4.2.3 All eight suspensions shall be shaken vigorously together in a flask to mix thoroughly and to break up any clumps of spor

33、es. 4.2.4 The suspension shall be used on the day of its preparation, and shall not be stored for future use. 4.3 Preparation of the nutrient solution It shall consist of a solution of the following materials in distilled water. The quantities are amounts per litre of water. Modified Czapek-Dox nutr

34、ient solution with saccharose The solution shall be sterilized in an autoclave at115 C for 30 min. The pH solution shall then be measured and adjusted, if necessary, by addition of a 0,01 N sodium hydroxide solution to obtain a pH between 6,0 and 6,5 after sterilization. 4.4 Control strips They shal

35、l be made of white filter paper which has not been exposed to any fungicidal treatment. They shall be placed in glass dishes and covered with the nutrient solution (see 4.3). They shall be removed from this solution and allowed to drain immediately before use. The strips shall be prepared on the day

36、 the test commences. A freshly prepared nutrient solution shall be used for preparing each group of control strips. These strips shall be sprayed with the same suspension as that used for the specimens. 5 Method These tests shall only be carried out by approved laboratories. All specimens, reference

37、 specimens and a group of three control strips shall be put in separate containers. All containers shall be placed together in the same test chamber. The specimens and control strips shall be placed in the chamber within 15min after spraying with spores. They shall not be unduly disturbed during the

38、 test, except for opening container lids and the chamber door each week. The test chamber used shall maintain a temperature between 28C and 30C. Any periodic variation in temperature due to action of the thermostat shall not exceed 1C/h. Each specimen and control strip shall be put in a glass or pla

39、stic container (e.g. a Petri dish) with a lid. The container shall permanently contain water to maintain a relative humidity greater than 90 % inside. The specimens shall not be immersed or splashed by the water. The container lid shall be removed for a few seconds once per week to ensure a regular

40、supply of oxygen in the air to the growing moulds. Potassium dihydrogen orthophosphate (KH 2 PO 4 ) 0,7 g Potassium monohydrogen orthophosphate (K 2 HPO 4 ) 0,3 g Magnesium sulphate (Mg SO 4 7H 2 O) 0,5 g Sodium nitrate (NaNO 4 ) 0,2 g Potassium chloride (KCl) 0,5 g Ferrous sulphate (FeSO 4 7H 2 O)

41、0,01 g Saccharose 30 gEN2591-306:1998 BSI 04-1999 5 The first opening shall be 7 d after spraying. If no mould growth is visible on any control strip, the test shall be considered invalid and shall be repeated. 5.1 Initial measurements (if applicable) They shall be carried out as specified. If mould

42、 growth on the control strips indicates that the conditions are suitable and the moulds viable, the test shall continue for the time specified. If the chamber, or a container, becomes contaminated and must be cleaned, the preferred method is to heat it in a moisture saturated atmosphere at 120C for

43、1 h. Where heating is not possible, dry the chamber or the container and fumigate it with propylene oxide, finally washing it with water containing a detergent and ventilating it well to remove all oxide fumes. 5.2 Procedure 5.2.1 Method A Expose the specimens to the suspensions which shall be suppl

44、ied with a medium containing no assimilable carbon. Mould growth can only take place to the detriment of the specimen component materials. If there are no edible materials, spores can not develop and there will be no attack. The period of exposure shall be one of the following: 28 d: assessment of t

45、he mould growth by a single visual examination; 84 d: in addition to assessment of the mould growth, assessment of the damage due to mould growth by the specified measurements. If 84 d exposure is specified, two groups of specimens shall be required: first group: specimens; second group: reference s

46、pecimens for damp heat test. The temperature and relative humidity conditions shall be identical for both tests, (mould growth and damp heat). 5.2.1.1 Sprayings Sprayings shall be done with pipettes or spray guns depending on the nature of the spray, but with identical characteristics. The nozzle, i

47、n particular, shall be large enough not to be blocked by fragments of mycelium. 5.2.1.2 Specimens (28 d or 84 d) They shall be sprayed with the suspension according to4. 5.2.2 Method B Expose the specimens to the specified suspensions deposited on a nutrient medium allowing mould to grow previously

48、applied to them. Even if the specimens do not have any nutrient elements, mould growth may progress as well as the action of the products of their metabolism. The period of exposure (28 d or 84 d) shall be specified. Regardless of the period of exposure, mould growth shall be assessed by visual exam

49、ination and the damage to specimens by measurements. Three groups of specimens are required: first group: specimens; second group: reference specimens for damp heat test; third group: laboratory reference specimens which shall not be exposed to any test and to be used as reference for visual examination. The periods of exposure, the temperature and relative humidity conditions for the first group exposed to the mould growth test and the second group exposed to the damp heat tes