1、BRITISH STANDARD BS EN 872:2005 BS 6068-2.54:2005 Water quality Determination of suspended solids Method by filtration through glass fibre filters The European Standard EN 872:2005 has the status of a British Standard ICS 13.060.30 BS EN 872:2005 This British Standard was published under the authori
2、ty of the Standards Policy and Strategy Committee on 21 February 2005 BSI 21 February 2005 ISBN 0 580 45513 0 National foreword This British Standard is the official English language version of EN 872:2005. It supersedes BS EN 872:1996 which is withdrawn. The UK participation in its preparation was
3、entrusted by Technical Committee EH/3, Water quality, to Subcommittee EH/3/2, Physical, chemical and biochemical methods, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards whic
4、h 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 of the BSI Electronic Catalogue or of British Standards Online. This publicat
5、ion 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. aid enquirers to understand the text; present to the responsible international/
6、European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page
7、, pages 2 to 10, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 872 February 2005 ICS 13.060.30 Sup
8、ersedes EN 872:1996 English version Water quality - Determination of suspended solids - Method by filtration through glass fibre filters Qualit de leau - Dosage des matires en suspension - Mthode par filtration sur filtre en fibres de verre Wasserbeschaffenheit - Bestimmung suspendierter Stoffe - Ve
9、rfahren durch Abtrennung mittels Glasfaserfilter This European Standard was approved by CEN on 17 December 2004. 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 al
10、teration. 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 tra
11、nslation 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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece,
12、 Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: r
13、ue de Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 872:2005: EEN 872:2005 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle4 5 Apparatus .5
14、6 Reagents.5 7 Sampling and sample handling6 8 Procedure .6 9 Control 7 10 Calculation and report.7 11 Precision.7 Annex A (informative) Samples containing oil or other organic liquids9 Bibliography 10 EN 872:2005 (E) 3 Foreword This document (EN 872:2005) has been prepared by Technical Committee CE
15、N/TC 230 “Water analysis”, the secretariat of which is held by DIN. 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 August 2005, and conflicting national standards shall be withdrawn at the latest
16、 by August 2005. This document supersedes EN 872:1996. WARNING Persons using this document should be familiar with normal laboratory practice. This document does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appr
17、opriate safety and health practices and to ensure compliance with any national regulatory conditions. The evacuation of large glass vessels can cause dangerous implosions if the vessel is damaged by scratches etc. It should be ensured that the relevant safety precautions have been observed. Accordin
18、g to the CEN/CENELEC Internal Regulations, the 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,
19、 Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 872:2005 (E) 4 1 Scope This document describes a method for the determination of suspended solids in raw waters, waste waters and effluents by filtration through glass fib
20、re filters. The lower limit of the determination is about 2 mg/l. No upper limit has been established. Water samples are not always stable which means that the content of suspended solids depends on storage time, means of transportation, pH value and other circumstances. Results obtained with unstab
21、le samples need to be interpreted with caution. Floating oil and other immiscible organic liquids will interfere (see Annex A). Samples containing more than about 1 000 mg/l of dissolved solids can require special treatment (8.6). NOTE 1 The result of the determination depends to some extent on the
22、type of filter used (5.2). It is therefore recommended that the type of filter is specified. NOTE 2 The size distribution of particles in different samples can vary widely. Therefore there is no correlation between results obtained with filters of different pore width and no conversion factor can be
23、 given for the conversion of results obtained with one type of filter to another. 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
24、referenced document (including any amendments) applies. EN 25667-2:1993, Water quality Sampling Part 2: Guidance on sampling techniques (ISO 5667-2:1991). EN ISO 5667-3, Water quality Sampling Part 3: Guidance on the preservation and handling of samples (ISO 5667-3:2003). 3 Terms and definitions For
25、 the purposes of this document, the following terms and definitions apply. 3.1 suspended solids solids removed by filtration under specified conditions 3.2 dissolved solids substances remaining, after filtration and evaporation to dryness of a sample, under specified conditions 4.25.1 of ISO 6107-2:
26、1997 4 Principle Using a vacuum or pressure filtration apparatus the sample is filtered through a glass fibre filter. The filter is then dried at 105 C 2 C and the mass of the residue retained on the filter is determined by weighing. EN 872:2005 (E) 5 5 Apparatus 5.1 Equipment for vacuum or pressure
27、 filtration, to accommodate the selected filters (5.2). Equipment for membrane filtration can in most cases be used for other types of filters. The plate supporting the filter needs to have sufficient permeance to allow the water to pass freely. 5.2 Borosilicate glass fibre filters 5.2.1 The borosil
28、icate filters shall satisfy the following criteria shall not contain any binders; shall be circular and of the appropriate diameter to fit the filtering device (5.1); shall comprise a mass per unit area of between 50 g/m 2and 100 g/m 2 ; the loss of mass obtained in a blank test (5.2.2) shall be les
29、s than or equal to 0,017 mg/cm 2(for the more common diameter of 47 mm, this corresponds to a loss of mass less than or equal to 0,3 mg). 5.2.2 Blank test Check the loss of mass during filtration by running the procedure in Clause 8 but using 150 ml of distilled water instead of the sample. Check ea
30、ch box or batch of filters separately. Carry out the test 3 times, selecting 3 filters at random, to increase the sensitivity of the test. NOTE To remove water-soluble constituents, the filters may be prewashed. Individual or a small number of filters (less than 10) are prewashed by filtering 150 ml
31、 of distilled water through the filter(s) and then drying at 105 C for at least 1 h. It is recommended to bulk-wash filters by soaking in distilled water for several hours. The wash water is drained off and the filter dried at 105 C for at least 1 h or preferably overnight before use. Glass fibre fi
32、lters from different manufacturers can have somewhat different filtering characteristics. State the type of filter used and its manufacturer in the report (see Clause 10). 5.3 Drying oven, capable of maintaining a temperature of 105 C 2 C. 5.4 Analytical balance, capable of weighing to an accuracy o
33、f at least 0,1 mg. 5.5 Drying support of suitably surfaced material, to support the filters in the drying oven (5.3), e.g. Petri dishes. 6 Reagents 6.1 Reference suspension, microcrystalline cellulose, 500 mg/l. Weigh 0,500 g (oven dry basis) of microcrystalline cellulose (C 6 H 10 O 5 ) n , the gra
34、de used for thin layer chromatography (TLC), or equivalent, and transfer it quantitatively into a 1 000 ml volumetric flask and make up to the mark with distilled water. Shake the suspension well before use. The suspension may be stored for at least three months. NOTE The dry matter content of the m
35、icrocrystalline cellulose can be determined by drying a separate sample in an oven at 105 C 2 C. 6.2 Working reference suspension, = 50 mg/l. EN 872:2005 (E) 6 Shake the reference suspension (6.1) until it is completely uniform. With a minimum delay measure out 100 ml 1 ml into a 100 ml volumetric f
36、lask. Transfer the measured volume quantitatively into a 1 000 ml volumetric flask and make up to the mark with distilled water. Shake the suspension well before use. Prepare a fresh reagent daily. 7 Sampling and sample handling Obtain samples as described in the relevant sampling guidelines, such a
37、s EN 25667-2 and EN ISO 5667-3. Samples shall preferably be taken in bottles of transparent material. Avoid filling the bottles completely to allow efficient mixing by shaking the bottle. Analyse samples for the determination of suspended solids as soon as possible after sampling, preferably within
38、4 h. Store samples which cannot be analysed within 4 h in the dark at between 1 C and 5 C, but do not allow the sample to freeze. Interpret results obtained for samples that have been stored more than 2 days with caution. Samples for the determination of suspended solids shall not be preserved by an
39、y additives. If the time period from sampling to analysis exceeds 2 days, this shall be stated in the report as well as the conditions of storage. 8 Procedure 8.1 Allow the samples to attain room temperature. 8.2 Ensure that the filters fulfil the requirements given in 5.2.1. 8.3 Allow a filter to a
40、ttain moisture equilibrium with the air near the balance and weigh it to the nearest 0,1 mg using the balance (5.4). Take care to avoid dust contaminating the filter, for example by using a desiccator. 8.4 Place the filter, the smooth side down, in the funnel of the filtering device (5.1) and connec
41、t the device to a vacuum (or pressure) line. 8.5 Shake the sample bottle vigorously and immediately transfer in one stroke a suitable volume of sample to a measuring cylinder. If the sample is obtained in a completely filled bottle, mix the sample by transferring it “back and forth“ between two bott
42、les. Check that the second bottle is dry and free from contaminants before use. Select the sample volume so that the dry residue on the filter will be in the optimum range of the determination, which is between 5 mg and 50 mg. However, avoid sample volumes exceeding 1 l. To be valid, the result shal
43、l be based on a dry residue of at least 2 mg. Read the sample volume with an accuracy of 2 % or better. Sample volumes of less than 25 ml shall be determined by weighing. 8.6 Filter the sample and rinse the measuring cylinder with about 20 ml of distilled water and use this portion to wash the filte
44、r. Rinse the inner sides of the funnel with another 20 ml portion of distilled water. If the sample contains more than 1 000 mg/l of dissolved solids, repeat the washing of the filter with 3 portions each consisting of 50 ml of distilled water. Take care to wash the rim of the filter. NOTE The filte
45、ring normally is complete within less than 1 min. However, some types of waters contain materials that block the filter pores or reduce their width. This increases the filtering time and the results can become a function of the sample volume. If such blocking of the filter is observed, the determina
46、tion should be repeated with smaller volumes. The results should be interpreted with caution. Release the vacuum (or pressure) when the filter is almost dry. Carefully remove it from the funnel with a pair of forceps having flat ends. The filter may be folded if desired. Place the filter on the dryi
47、ng support (5.5) and dry it in the oven (5.3) at 105 C 2 C for at least 1 h and with a maximum of 14 h to 16 h. Remove from the oven and allow the filter to attain equilibrium with the air surrounding the balance and weigh it as before. EN 872:2005 (E) 7 9 Control Repeat the test procedure (see Clau
48、se 8) using 200 ml of the working reference suspension (6.2) as the sample. The recovery shall be between 90 % and 110 %. 10 Calculation and report 10.1 Calculation Calculate the content of suspended solids from the expression V a b ) ( 000 1 = where is the content of suspended solids, in milligrams
49、 per litre, mg/l; b is the mass of the filter after the filtration, in milligrams, mg; a is the mass of the filter before the filtration, in milligrams, mg; V is the volume of the sample, in millilitres, ml. If the sample has been weighed, consider 1 g as equivalent to 1 ml. 10.2 Report Report results below 2 mg/l as “below 2 mg/l“ and other results in milligrams per litre with two significant figures. The test report shall refer to this document a
