1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58penetration by sprayed liquid chemicals, emulsions and dispersions Atomizer testThe European Standa
2、rd EN 14786:2006 has the status of a British StandardICS 13.340.10Protective clothing Determination of resistance to BRITISH STANDARDBS EN 14786:2006BS EN 14786:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2006 BSI 2006ISBN 0 5
3、80 48498 Xrequest to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility
4、of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations.Summ
5、ary of pagesThis document comprises a front cover, an inside front cover, the EN title page, pages 2 to 17 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA list of organizations
6、 represented on this subcommittee can be obtained on present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.Nationa
7、l forewordThis British Standard is the official English language version of EN 14786:2006.The UK participation in its preparation was entrusted by Technical Committee PH/3, Protective clothing, to Subcommittee PH/3/3, Protective clothing from chemicals and radioactive contamination , which has the r
8、esponsibility to: aid enquirers to understand the text;EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14786April 2006ICS 13.340.10English VersionProtective clothing - Determination of resistance to penetrationby sprayed liquid chemicals, emulsions and dispersions -Atomizer testVtements de protect
9、ion - Dtermination de la rsistance la pntration par les produits chimiques liquidespulvriss, les mulsions et les dispersions - Essai depulvrisationSchutzkleidung - Bestimmung des Widerstandes gegenDurchdringung von flssigen gespritzten Chemikalien,Emulsionen und Dispersionen - SpritzverfahrenThis Eu
10、ropean Standard was approved by CEN on 16 March 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references con
11、cerning such nationalstandards 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 translationunder the responsibility of a CEN member into its own l
12、anguage and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, M
13、alta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of explo
14、itation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14786:2006: EEN 14786:2006 (E) 2 Contents Page Foreword 3 Introduction4 1 Scope .5 2 Normative references .5 3 Terms and definitions.5 4 Principle.5 5 Apparatus 6 5.1 Test chamber.6 5.2 Atomizer.8 5.3 Motor d
15、riven syringe.11 5.4 Air supply 11 6 Reagents and materials11 6.1 Absorbent11 6.2 Solvent for extraction .11 7 Test conditions and procedure11 7.1 General 11 7.2 Preparatory tests.11 7.2.1 Determination of the amount of liquid contaminating the sample area11 7.2.2 Determination of the extraction eff
16、iciency12 7.2.3 Blank test.12 7.3 Preparation and conditioning of test specimens12 7.4 Test procedure 12 8 Calculation of test results 12 9 Test report .13 Annex A (informative) Example of test 14 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU
17、 Directive 89/686/EEC16 Bibliography.17 EN 14786:2006 (E) 3 Foreword This European Standard (EN 14786:2006) has been prepared by Technical Committee CEN/TC 162 “Protective clothing including hand and arm protection and lifejackets”, the secretariat of which is held by DIN. This European Standard sha
18、ll be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2006, and conflicting national standards shall be withdrawn at the latest by October 2006. This European Standard has been prepared under a mandate given to CEN by th
19、e European Commission and the European Free Trade Association, and supports essential requirements of EU Directive 89/686/EEC. For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this European Standard. According to the CEN/CENELEC Internal Regulations, the
20、national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland
21、, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 14786:2006 (E) 4 Introduction This European standard specifies a test method to measure a penetration index for protective clothing materials against atomized emulsions and dispersions of liquid chemicals, e.g
22、. pesticides used in agricultural crop spraying. The data may be used as a guide for screening protective clothing materials but the results of the test are affected by the physical properties of the test chemical, e.g. low volatility chemicals. Clothing, which has been developed from materials sele
23、cted by means of this method of test, should be used only in well-defined circumstances, i.e. when an evaluation of the finished item has indicated an acceptable level of performance (e.g. in laboratory and field testing of a garment, consideration of exposure levels to specified chemicals etc.). Cl
24、othing made of these materials is not for use as the sole means of protection where resistance to permeation by chemicals at the molecular level (to be determined by EN ISO 6529) is essential and where a complete barrier to liquid (or gaseous chemicals) is required (e.g. risk of exposure to massive
25、and forceful discharges of concentrated liquid chemicals). The potential performance levels of materials as assessed by the test method described in this standard are intended to be used in product specifications for protective apparel against atomized liquids, emulsified and dispersed chemicals. EN
26、 14786:2006 (E) 5 1 Scope This European Standard specifies a test method to determine the resistance of textile materials against penetration by atomized liquid chemicals, emulsions and dispersions. These materials are intended to be used in both limited-use and reusable protective clothing. The pen
27、etration is expressed in percent, as ratio of the amounts of chemical applied and retained by the textile. The methods of quantitative physico-chemical analysis used for mass detection will depend on the chemical under test. 2 Normative references The following referenced documents are indispensable
28、 for the application of this European Standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 22768-1, General tolerances - Part 1: Tolerances for linear and angular dimensions withou
29、t individual tolerance indications (ISO 2768-1:1998) 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 penetration process by which a chemical flows through holes or essential openings in the material. NOTE The holes may be the result
30、of mechanical damage 3.2 permeation the process by which a chemical moves through a protective clothing material on a molecular level. NOTE Permeation involves: sorption of the molecules of the chemical into the contacted (outside) surface of the material; diffusion of the sorbed molecules in the ma
31、terial, and desorption of the molecules from the opposite (inner) surface of the material. 4 Principle A test specimen is contaminated by a small quantity of atomized liquid chemical, emulsion or dispersion, injected by a two-phase nozzle operated by a microprocessor controlled step motor. Part of t
32、he chemicals will penetrate and wet the test specimen. The flow of chemical passing through the material will be taken up by an absorbent under the test specimen (see Figure 1 for a schematic representation of the test equipment). After 30 min. exposure time the textile and the adsorbent are extract
33、ed and analysed in order to determine the amounts of chemical retained and passed through .The extraction efficiency shall be proven and should be larger than 95 %. Depending on the type of chemical different techniques such as e. g. high pressure liquid chromatography (HPLC) or gas chromatography (
34、GC) are used for the quantitative analysis. The penetration of a protective clothing material is defined as the ratio of the mass of chemical penetrated to the mass of chemical applied. EN 14786:2006 (E) 6 Key a Detail X: see Figure 6 1 Fastenings 2 Controlled step motor 3 Syringe with test chemical
35、 4 Two-phase nozzle 5 Nozzle holder 6 Covering cylinder 7 Mask 8 Textile specimen 9 Sorbent 10 Ground plate of specimen holder Figure 1 - Schematic representation of the test equipment 5 Apparatus 5.1 Test chamber The test chamber consists of the sample holder and a covering cylinder. The dimensions
36、 are given in Figure 2 to Figure 4. The sample holder consists of a ground plate and a mask. Both are made of stainless steel or chromium-plated brass (see Figure 2 and Figure 3). ground plate: the ground plate takes up the covering cylinder, the absorbent and the textile sample mask: the mask fixes
37、 the textile sample with a defined open area for the spray. The covering cylinder encapsulates the atomizer and test equipment. It is preferably made of glass to observe the spray-cone during application but may also be made of stainless steel or chromium-plated brass (see Figure 4). EN 14786:2006 (
38、E) 7 Dimension in millimetres General tolerances: EN 22768-1 General tolerances: EN 22768-1 Figure 2 - Dimensions of ground plate Figure 3 - Dimensions of sample holder mask EN 14786:2006 (E) 8 Dimensions in millimetres General tolerances: EN 22768-1 Figure 4 - Dimensions of covering cylinder 5.2 At
39、omizer The atomizer consists of a two-phase nozzle with magnetic valve and control unit. The nozzle is held up by and fixed to a nozzle holder (see Figure 5). The nozzle consists of the nozzle-body and the inside luer-lock needle with a connection to the syringe. The needle is 24 mm long with an int
40、ernal diameter of 0,35 mm. It is flush closed with the bottom of the nozzle body (see Figure 6 and Figure 7). EN 14786:2006 (E) 9 Dimensions in millimetres Key a counterbore General tolerances: EN 22768-1 Key a detail X of Figure 1 General tolerances: EN 22768-1 Figure 5 - Nozzle holder Figure 6 Two
41、 phase nozzle EN 14786:2006 (E) 10 Dimensions in millimetresKey a Conterbore 1 Luer-lock needle 2 Body parts of the two-phase nozzle General tolerances: EN 22768-1 Figure 7 Two - phase nozzle, details and dimensions EN 14786:2006 (E) 11 5.3 Motor driven syringe To ensure a continuous steady flow and
42、 a well repeatable volume a microprocessor controlled step motor is recommended as drive of the syringe. One-way or re-usable syringes (2 ml) should be used. The step motor shall guarantee a liquid discharge of 1 ml in (20 2) s. 5.4 Air supply Compressed air with a pressure of 300 hPa shall be used.
43、 The air supply is controlled by a microprocessor controlled magnetic valve which opens 50 ms before the syringe begins to move and stops 500 ms after the syringe stops. 6 Reagents and materials 6.1 Absorbent A suitable absorbent shall be used, depending on the type of chemical under test. NOTE Benc
44、hcote and -Cellulose filters are proven to be suitable materials. 6.2 Solvent for extraction Depending on the chemical under test a suitable solvent shall be used to extract the chemical from the test specimen and from the absorbent (e.g. acetonitrile). The amount of solvent needed depends on the de
45、tectable concentration range of the subsequent analysis (typical 25 ml to 50 ml). Mass detection requires analytical procedures like gas chromatography (GC) or high pressure liquid chromatography (HPLC). 7 Test conditions and procedure 7.1 General NOTE 1 Depending on the volatility and the toxicity
46、of the chemicals the test should be carried out under a laboratory hood. Safety regulations should be observed. A set of preparatory tests is carried out to determine the amount of liquid contaminating the specimen, the efficiency of extraction and the analysis of an uncontaminated specimen (blind t
47、est). The test procedure itself consists of 3 steps: applying the chemical; extraction; analysis (quantitative mass detection). NOTE 2 Analysis may follow later if the extracts can be stored without losses or degradation of the chemicals. If necessary, pre-tests should be done to define the conditio
48、ns of storage (e.g. refrigerator at 4 C, freezer at 20 C). 7.2 Preparatory tests 7.2.1 Determination of the amount of liquid contaminating the sample area The physical properties of the liquid, emulsion or dispersion influence the spray cone. This results in different amounts of liquid contaminating
49、 the test specimen. This amount shall however be fixed to (0,5 0,05) ml. The actually applied volume and hence the time of application shall be calibrated by spraying the mixture on a sample of glass or coated filter which is weighed to determine the amount of contamination. EN 14786:2006 (E) 12 NOTE It is assumed that the density of the sprayed solution is that of pure water, since it is a very diluted solution. 7.2.2 Determination of the extraction efficiency A specimen is contaminated with (0,
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