1、DEUTSCHE NORM Decem ber 1995 Determination of permeability of fabrics to air English version of DIN EN IS0 9237 (IS0 9237 : 1995) DIN EN IS0 9237 This standard incorporates the English version of Is0 9237. ICs 59.080.30 Descriptors: Textiles, fabrics, testing, air permeability. Supersedes DIN 53887,
2、 August 1986 edition. Textilien; Bestimmung der Luftdurchlssigkeit von textilen Flchengebilden (IS0 9237:1995) European Standard EN IS0 9237: 1995 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This standard has been published in accordance with a decision
3、 taken by CENTTC 248 to adopt, without alteration, International Standard IS0 9237 as a European Standard. The responsible German body involved in its preparation was the Normenausschu Materialprfung (Materials Testing Standards Committee). The DIN Standards corresponding to the International Standa
4、rds referred to in clause 2 of the EN are as follows: IS0 139 DINEN20139 IS0 48 DIN 53519-1 IS0 10012 DIN IS0 10012-1 Amendments In comparison with DIN 53887, August 1986 edition, the following amendments have been made. a) The standard atmospheres specified in IS0 139 shall be used for conditioning
5、 and testing the samples. b) The test area of 10 cm2 has been reduced to 5 cm2. c) Test equipment provided with a guard ring device may be used to prevent leakage of air around the edges of the specimen. d) Recommendations for the measurement conditions to be used when testing fabrics for parachutes
6、 are no longer specified. Previous editions DIN 53887: 1966-11, 1977-06, 1986-08. Standards referred to (and not included in Normative references) DIN 5351 9-1 Determination of indentation hardness (IHRD) of soft rubber using standard specimens DIN EN 20 139 Textiles; standard atmospheres for condit
7、ioning and testing EN comprises 5 pages. uth Verlag GmbH, Berlin, has the exclusive right of sale for German Standards (DIN-Normen). DIN EN IS0 9237 Eng/. Price group I - -. 05.96 Sales No. 11 06 EUROPEAN STANDARD NORME EUROPENNE EUROPAISCHE NORM EN IS0 9237 June 1995 ICs 59.080.30 Descriptors: Text
8、iles, fabrics, testing, air permeability. English version Textiles Determination of permeability of fabrics to air (IS0 9237 : 1995) Textiles; dtermination de la permabilit lair des toffes (IS0 9237: 1995) Textilien; Bestimmung der Luftdurchls- sigkeit von textilen Flchengebilden (IS0 9237 : 1995) T
9、his European Standard was approved by CEN on 1995-05-05 and is identical to the IS0 Standard as referred to. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterat
10、ion. Up-to-date lists and bibliographical 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 translat
11、ion under the responsibility of a CEN member 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, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
12、Netherlands, Norway, Portugal, 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, 8-1050 Brussels O 1995. Copyright reserved to all CEN members. Ref. No. EN I
13、S0 9237:1995 E Page 2 EN IS0 9237:1995 Foreword International Standard IS0 9237:1995 Textiles; determination of the permeability of fabrics to air, which was prepared by ISOTTC38 Textiles of the International Organization for Standardization, has been adopted by Technical Committee CENTTC248 Textile
14、s and textile products as a European Standard. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, and conflicting national standards withdrawn, by December 1995 at the latest. In accordance with the CENKENELEC Intern
15、al Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of the In
16、ternational Standard IS0 9237: 1995 was approved by CEN as a European Standard without any modifica- tion. 1 Scope This International Standard describes a method for measuring the permeability of fabrics to air and is ap- plicable to most types of fabrics, including industrial fabrics for technical
17、purposes, nonwovens and made-up textile articles that are permeable to air. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publi- cation, the editions indicated were valid.
18、All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most re- cent editions of the standards indicated below. Members of IEC and IS0 maintain registers of cur- rently valid International St
19、andards. IS0 48:1994, Rubber, vulcanized or thermoplastic - Determination of hardness (hardness between 10 IRHD and 100 IRHDI. IS0 139: 1 973, Textiles - Standard atmospheres for conditioning and testing. IS0 1 O01 2-1 : 1992, Quality assurance requirements for measuring equipment - Part I: Metrolog
20、ical confirmation system for measuring equipment. 3 Definition For the purposes of this International Standard, the following definition applies. 3.1 air permeability: Velocity of an air flow passing perpendicularly through a test specimen under speci- fied conditions of test area, pressure drop and
21、 time. 4 Principle The rate of flow of air passing perpendicularly through a given area of fabric is measured at a given pressure difference across the fabric test area over a given time period. 5 Sampling Select samples either in accordance with the pro- cedure laid down in the material specificati
22、on for the fabric, or as agreed between the interested parties. In the absence of specification, follow the example of sampling given in annex B. 6 Atmospheres for conditioning and testing The atmospheres for preconditioning, conditioning and testing shall be as specified in IS0 139. 7 Apparatus Met
23、rological confirmation of the test apparatus shall be carried out in accordance with IS0 1001 2-1. 7.1 Circular specimen holder, with an orifice al- lowing the test to be carried out on an area of 5 cm, 20 cm, 50 cm2 or 100 cm. The tolerance on the test area shall not exceed f 0.5 %. NOTE 1 larly fo
24、r large test surfaces, is recommended. Adequate support of the test specimen, particu- 7.2 Means for clamping, to secure the specimen without distortion. NOTE 2 Care should be taken to prevent leakage of air Page 3 EN IC0 9237: 1995 around the edges of the test specimen. Alternatively the leakage ma
25、y be measured separately and subtracted from the test results. 7.3 Guard ring device, to prevent leakage, for op- tional use in conjunction with the clamping means (7.2), (see A.2.1). 7.4 Pressure gauge or manometer, connected to the test head to indicate a pressure drop across the specimen test are
26、a of 50 Pa, 100 Pa, 200 Pa or 500 Pa, with an accuracy of at least 2 %. 7.5 Means for drawing a steady flow of air at controlled temperature and humidity through the specimen holder and for adjusting the flowrate to produce a pressure drop across the specimen of be- tween 50 Pa and 500 Pa. 7.6 Flowm
27、eter, volumetric counter or measuring aperture, indicating the rate of air flow in cubic decimetres per minute (litres per minute) with an ac- curacy of at least f 2 %. NOTE 3 Flowmeters or volumetric counters measuring the rate of air flow in cubic centimetres per second (or other suitable units) m
28、ay be used if the required accuracy of at least I 2 % is maintained. 8 Conditioning of samples and test conditions Prior to test the samples shall be conditioned and the test performed in the standard atmosphere for testing (see clause 6). Recommended conditions for the test are: test surface area:
29、20 cm2; pressure drop: 100 Pa for apparel fabrics; pressure drop: 200 Pa for industrial fabrics. In cases where these pressure drops cannot be achieved or are not appropriate, an alternative pres- sure drop of 50 Pa or 500 Pa may be used and/or an alternative test area of 5 cm2, 50 cm2 or 1 O0 cm2 m
30、ay be chosen, if agreed between the interested parties. NOTE 4 For comparison of results it is recommended to perform the test with the same test area and pressure drop. 9 Test procedure NOTE 5 the test is given in annex A. Advice on checking calibration and conducting Mount the test specimen in the
31、 circular specimen holder (7.1) with sufficient tension to eliminate wrin- kles, if any, taking care that the fabric is not distorted in its own plane. Avoid selvedges and areas with creases or folded places. For fabrics for which the air permeability may be different between the two faces of the fa
32、bric, specify in the test report see 11 a)2) which face was tested. Clamp specimens coated on one side with the coating towards the lower pressure side to prevent air leakage. Start the suction fan or other means (7.5) to force the air through the test specimen and adjust the flow of air gradually t
33、ill a pressure drop, as recommended above, is achieved across the test area of the fabric. Record the air flow (see 7.6) after at least 1 min or until steady conditions are achieved. NOTE 6 Some devices, e.g. volumetric counters, may need a volume of air flow of about 10 dm3 to assure the required a
34、ccuracy. Repeat the test at different locations on the sample at least 1 O times under the same conditions. 10 Calculation and expression of results 10.1 Calculate the arithmetic mean of the individual readings and the coefficient of variation (to the near- est 0.1 %), stating the 95 % confidence in
35、terval. 10.2 Calculate the air permeability, R. expressed in millimetres per second, using the equation 4V R=-x 167 A where qV is the arithmetic mean flowrate of air, in cubic decimetres per minute (litres per minute); A is the area of fabric under test, in square centimetres: 167 is the conversion
36、factor from cubic decimetres (or litres) per minute per square centimetre to millimetres per sec- ond. 10.3 For open fabrics and nonwovens, the air per- meability R may be expressed in metres per second using the equation 4v A R = - x 0,167 where all information necessary for complete identi- ficati
37、on of the sample tested and, if required, indication of the direction of air flow through the fabric; 3) test surface area used, in square centimetres; 4) pressure drop used, in pascals; 5) number of specimens tested; 6) the conditioning and testing atmospheres used; 7) any deviation from the proced
38、ure specified. b) test results: 1) mean air permeability E, in millimetres per second or metres per second, as applicable; 2) coefficient of variation, in percent; 3) 95 % confidence interval, in millimetres per second or metres per second, as applicable. Annex A (informative) Advice on checking the
39、 calibration and conducting the test A.l Checking the apparatus and calibration It is advisable to check the calibration and the proper functioning of the apparatus weekly if in constant use, prior to testing if used infrequently, and after the ap- paratus has been moved or repaired. The calibration
40、 of the apparatus should be checked periodically against a primary reference standard, at intervals of no greater than 12 months. The calibration of the pressure gauge (7.4) should also be checked periodically. A calibration check plate with test aperture of known air permeability at given pressure
41、drop should be used for checking the calibration. Ensure the reproducibility of the exact position of the check plate in the circular specimen holder (7.1) to avoid any air leakage. Means for checking the calibration recommended for specific types of apparatus should be used in accord- ance with the
42、 specification of the apparatus and the required accuracy of the test. A.2 Conducting the test A.2.1 Edge leakage may be prevented by means of an annular guard ring (7.3). The pressure drop acrosss the guard ring is measured by a separate pressure gauge or manometer (7.4); the air drawn through the
43、guard ring should not pass through the flowmeter (7.6). The pressure drops across the test and the guard ring surfaces are equalized, so that no air can pass edgewise either to or from the test sur- faces. If the measuring device is not equipped with a guard ring, the rate of edge leakage can be det
44、ermined by covering the sample with a rubber plate of the same size as the sample. Rubber plates 1 mm to 2 rnm thick, having a hardness of 65 IRHD to 70 IRHD when tested in accordance with IS0 48, have been found to be suitable. A.2.2 Clamps on the fabric surface should be faced with a suitable grad
45、e of rubber (see 7.2). Gaskets 2,5 mm thick and having a hardness of 65 IRHD to 70 IRHD when tested in accordance with IS0 48 have been found to be suitable. A.2.3 Care should be taken when clamping the specimen to ensure that it is not distorted or stretched. Page 5 EN IC0 9237: 1995 Number of piec
46、es in shipment or lot Annex B (i n f o r m a t ive) Minimum number of pieces in bulk sample Suggested sampling procedure 11 to 30 31 to 75 B.l Preparation of bulk sample (number B.2 Preparation of laboratory samples of pieces from a shipment or lot) To prepare the bulk sample, take at random from th
47、e shipment or lot at least the appropriate number of pieces shown in table B.1, Ensure that no piece that shows signs of damage or dampness incurred during transit is included in the bulk sample. From each piece comprising the bulk sample, cut (from a Position chosen at random but at least 3 m from an end of the Piece) a laboratOb sample of length at least 1 rn and of full width. Ensure that areas that are creased or that have a visible fault are not included in a laboratory sample. 3 4 I 3 76 I 5
