EN 15761-2009 en Pre-shaped growing media - Determination of length width height volume and bulk density《预成形生长介质 长度 宽度 高度 体积和体密度的测定》.pdf

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1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 15761:2009Pre-shaped growing media Determination of length,width, height, volume and bulkdensityBS EN 15761:2009 BRITISH STANDARDNational forewordThis British Standard is t

2、he UK implementation of EN 15761:2009.The UK participation in its preparation was entrusted to TechnicalCommittee AW/20, Top soil and other growing media.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all

3、the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 61954 0ICS 65.080Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy

4、 Committee on 31 July 2010Amendments issued since publicationDate Text affectedBS EN 15761:2009EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15761 December 2009 ICS 65.080 English Version Pre-shaped growing media - Determination of length, width, height, volume and bulk density Supports de cu

5、lture prforms - Dtermination de la longueur, de la largeur, de la hauteur, du volume et de la masse volumique apparente Vorgeformte Kultursubstrate - Bestimmung von Lnge, Breite, Dicke, Volumen und Schttdichte This European Standard was approved by CEN on 1 November 2009. CEN members are bound to co

6、mply 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 bibliographical references concerning such national standards may be obtained on application to the CEN Manag

7、ement Centre 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 member into its own language and notified to the CEN Management Centre has the same status as t

8、he official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slova

9、kia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2009 CEN All rights of exploitation in any form and by any means reserved worldwide

10、for CEN national Members. Ref. No. EN 15761:2009: EBS EN 15761:2009EN 15761:2009 (E) 2 Contents Page Foreword . 3Introduction . 41 Scope 52 Normative references 53 Terms and definitions . 54 Principle . 65 Apparatus . 66 Procedure . 66.1 Accuracy 66.2 Number of measurements 66.3 Test procedure 76.3.

11、1 General . 76.3.2 Test specimens with holes or grooves . 76.4 Determining the weight . 77 Calculations and expression of results 77.1 Length, width and height 77.2 Volume 77.2.1 Accuracy 77.2.2 Test specimens with no recesses . 77.2.3 Test specimens with recesses . 77.3 Bulk density . 88 Precision

12、89 Test report 8Annex A (informative) Results of an inter-laboratory trial 10A.1 Trials . 10A.2 Results 11Bibliography 12BS EN 15761:2009EN 15761:2009 (E) 3 Foreword This document (EN 15761:2009) has been prepared by Technical Committee CEN/TC 223 “Soil improvers and growing media”, the secretariat

13、of which is held by BSI. 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 June 2010, and conflicting national standards shall be withdrawn at the latest by June 2010. Attention is drawn to the poss

14、ibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries a

15、re bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Swe

16、den, Switzerland and the United Kingdom. BS EN 15761:2009EN 15761:2009 (E) 4 Introduction This European Standard has been produced so that there is a standard method to measure and weigh pre-shaped growing media and to calculate the volume and bulk density. The volume of growing media is a useful at

17、tribute for growers and is critical for ensuring plants have sufficient growing media for their root system. The bulk density is crucial as the reporting of all chemical analyses is expressed in units of weight per volume, and the volume is determined from the weight of the sample used for the chemi

18、cal analyses. Pre-shaped growing media is generally at present made from Stonewool or Rockwool or mineral wool. They are known by various names, typically: “plugs“ are small blocks used for seedlings, which are generally cylindrical in shape and with a diameter from 20 mm; once the seed has germinat

19、ed the seedling in the plug may then be placed into “blocks“; “blocks“ may have holes to take plugs and can vary in size from 40 mm 40 mm 40 mm up to 100 mm 200 mm 65 mm; they are generally used for propagation purposes; “slabs“ are used for growing vegetables and range in size from 370 mm 240 mm 10

20、0 mm to 2 000 mm 200 mm 75 mm. It is anticipated that this standard will be developed to encompass other new pre-shaped growing media in due course, e.g. coir blocks. BS EN 15761:2009EN 15761:2009 (E) 5 1 Scope This European Standard describes a method of determination of length, width, height, volu

21、me and bulk density of rectangular pre-shaped growing media. In this standard “pre-shaped growing media“: includes solid, regular shaped, stable growing media sold, which are ready for use as a growing media, where the dimensions and corners are stable, and the surfaces and edges are perpendicular t

22、o each other including mineral wool and polyurethane products; does not include solid growing media that has to be hydrated for it to form, varies in dimension with varying water content for example coir or peat slabs or growing bags. The minimum linear dimension (length, width or height) for blocks

23、 to which this standard applies is 40 mm, and the maximum dimension is 2 000 mm. 2 Normative 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 r

24、eferenced document (including any amendments) applies. CR 13456:1999, Soil improvers and growing media Labelling, specifications and product schedules 3 Terms and definitions For the purposes of this document, the terms and definitions given in CR 13456:1999 and the following apply. 3.1 length l lon

25、ger linear dimension of the major surface of the test specimen 3.2 width w shorter linear dimension of the major surface of the test specimen measured at right angles to the length 3.3 height h linear dimension measured perpendicularly to the length and the width planes 3.4 depth d linear dimension

26、measuring how deep recess intrude into the media 3.5 bulk density indication of how much 1 l of the product weighs, with the volume being determined in a standardized way NOTE The bulk density is expressed in grams per litre (g/L) or in kilograms per cubic metre (kg/m). BS EN 15761:2009EN 15761:2009

27、 (E) 6 4 Principle The test specimen is placed on a flat surface and measurements for length, width and height are taken. The volume is calculated from these dimensions and, after the determination of the weight, the bulk density is calculated. 5 Apparatus 5.1 Flat surface, horizontal, flat stable s

28、urface, e.g. table top, which is large enough for the test specimen and the measuring devices. 5.2 Metal rule or metal tape, graduated in millimetres and permitting reading to 0,5 mm or less. NOTE Measures conforming to the requirements of OIML R35-1:2007, Material measures of length for general use

29、. Part 1: Metrological and technical requirements 1, Class II are appropriate. This can be obtained from http:/www.oiml.org/publications/. 5.3 Height gauge, having an accuracy of at least 0,5 mm. 5.4 Pressure plate, square with a flat base and having sides of dimensions 100 mm x 100 mm, which weighs

30、 (50 1) g. NOTE Any other linear measuring device may be used if the results can be determined to within 0,5 mm. 5.5 Balance, having an accuracy of 0,1 g. NOTE Any balance conforming to the requirements of OIML R76-1:2006, Non-automatic weighing instruments. Part 1: Metrological and technical requir

31、ements Tests 2, Class II is appropriate. This can be obtained from http:/www.oiml.org/publications/. 6 Procedure 6.1 Accuracy Record all dimensional measurements to the nearest 0,5 mm or less. Record weight to the nearest 0,1 g or less. 6.2 Number of measurements For measurement of a nominal dimensi

32、on of 150 mm or less, make one measurement using the pressure plate and the height gauge. Position the pressure plate centrally on the test specimen, covering the maximum area possible. For measurement of a nominal dimension of more than 150 mm or less than 600 mm, make two measurements at one-third

33、 and two-third intervals laterally across the surface being measured, using an appropriate rule or tape. For measurement of a nominal dimension of more than 600 mm, make three measurements at one-quarter, one-half and three-quarter intervals laterally across the surface being measured, using an appr

34、opriate rule or tape. BS EN 15761:2009EN 15761:2009 (E) 7 6.3 Test procedure 6.3.1 General Lay the test specimen carefully on a flat surface. Determine the linear measurements by making the required number of measurements (6.2) between undamaged edges of the test specimen, keeping the tape or rule p

35、erpendicular to the edge. 6.3.2 Test specimens with holes or grooves If the test specimen has holes or grooves, such as a mineral wool block for culturing, then determine the volume of these recesses for subtracting from the external volume. Using the metal rule or tape (5.2), determine the length,

36、width and determine the depth of each rectangular recess at two points on each axis. Determine the diameter and depth of each cylindrical recess at two points for each axis. Ensure the depth is measured to the major recessed plane, and not to the depth of any guide hole used to drill the recessed ho

37、le. If the recess is neither rectangular nor cylindrical, then determine its volume in a mathematically correct manner by using the average of at least two measurements per axis. 6.4 Determining the weight After determining length, width and height (6.2), determine the weight of the test specimen us

38、ing the balance (5.5). 7 Calculations and expression of results 7.1 Length, width and height Use the recorded values of the length, width and height of the test specimen, which are all expressed in millimetres, to calculate the mean values for l, w and h. Round each mean to the nearest millimetre. 7

39、.2 Volume 7.2.1 Accuracy Record all values for volume to the nearest cubic millimetre, and then divide by 106to obtain the volume in litres. Record to four significant figures. 7.2.2 Test specimens with no recesses Determine the volume by multiplying the values or, where more than one value has been

40、 determined, the mean values for the length, width and height measurements. 7.2.3 Test specimens with recesses In the case of test specimens that have recesses, e.g. rock wool blocks, subtract the volume of plant holes and grooves from the externally measured volume. Calculate the volume of the rece

41、sses in the following way: In the case of a rectangular recess, substitute the mean values for the length (l), width (w) and depth (d) into the following formula: v = l w d (1) where BS EN 15761:2009EN 15761:2009 (E) 8 v is the volume, expressed in cubic millimetres (mm3); l is the length, expressed

42、 in millimetres (mm); d is the depth, expressed in millimetres (mm); w is the width, expressed in millimetres (mm). In the case of a cylindrical recess, substitute the mean values for the diameter (D) and depth (d) into the following formula: v = 0,25 D2 d (2) where v is the volume, expressed in cub

43、ic millimetres (mm3); D is the diameter, expressed in millimetres (mm); d is the depth, expressed in millimetres (mm). 7.3 Bulk density Calculate the bulk density, in grams of substrate per litre. Quote the mean results to three significant figures in grams per litre or kilograms per cubic metre, wh

44、ich are numerically the same. Vm=d (3) where mdis the mass of the test specimen, expressed in grams (g); V is the volume of the test specimen, expressed in litres (L). 8 Precision Perform the analysis on the basis of a minimum of five replicates for mats and twenty replicates for blocks that have be

45、en taken randomly from each batch. Record the results for each replicate. NOTE 1 Test specimens are randomly taken. NOTE 2 Typical performance characteristics for precision and accuracy are shown in Table A.1. 9 Test report Include the following information in the test report: a) a reference to this

46、 Standard; b) a complete identification of the test specimen(s); c) the results of the determinations; BS EN 15761:2009EN 15761:2009 (E) 9 d) any deviations from the procedure specified, as well as any other factor that might have affected the results. NOTE The test report may be prepared separately

47、 or in conjunction with the test report of the subsequent chemical and physical analyses. BS EN 15761:2009EN 15761:2009 (E) 10 Annex A (informative) Results of an inter-laboratory trial A.1 Trials An inter-laboratory trial was organized on 15 August 2007 to test the procedures specified in this stan

48、dard. In this trial a number of laboratories, as given below, determined the length, width, height and, volume and from this data calculated the bulk density of an individual test specimen. This was carried out on five types of product, and the results are given in Table A.1 as follows. Table A.1 Su

49、mmary of the results of an inter-laboratory trail for the determination of bulk density Sample 1 2 3 4 5 Number of laboratories retained after eliminating outliers 5 5 5 5 5 Number of outliers (laboratories) 0 0 0 0 0 Mean value g/L 78,5 68,9 69,7 76,7 55,5 Repeatabilityastandard deviation, srg/L 0,22 0,48 0,42 0,34 0,24 Repeatabilityarelative standard deviation % 0,28 0,70 0,60 0,44 0,43 Repeatabilityalimit, r = 2,8 sr