BS EN ISO 19458-2006 Water quality - Sampling for microbiological analysis《水质 微生物分析的抽样》.pdf

1、ICS 13.060.45g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58analysisThe European Standard EN ISO 19458:2006 has the status of a British Standard Wa

2、ter quality Sampling for microbiological BRITISH STANDARDBS EN ISO 19458:2006BS EN ISO 19458:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 September 2006 BSI 2006ISBN 0 580 49136 6Amendments issued since publicationAmd. No. Date Comm

3、entscontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of EN ISO 19458:2006. The UK participation in its preparation was

4、entrusted by Technical Committee EH/3, Water quality, to Subcommittee EH/3/4, Microbiological methods.A list of organizations represented on EH/3/4 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a EUROPEAN STANDARDNORME EUROPE

5、NNEEUROPISCHE NORMEN ISO 19458August 2006ICS 13.060.45English VersionWater quality - Sampling for microbiological analysis (ISO19458:2006)Qualit de leau - chantillonnage pour analysemicrobiologique (ISO 19458:2006)Wasserbeschaffenheit - Probenahme fr mikrobiologischeUntersuchungen (ISO 19458:2006)Th

6、is European Standard was approved by CEN on 1 July 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

7、concerning 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 ow

8、n language 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

9、, Malta, 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 ex

10、ploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 19458:2006: EForeword This document (EN ISO 19458:2006) has been prepared by Technical Committee ISO/TC 147 “Water quality“ in collaboration with Technical Committee CEN/TC 230 “Water analysis“, the se

11、cretariat 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 February 2007, and conflicting national standards shall be withdrawn at the latest by February 2007. According to

12、 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, Lux

13、embourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 19458:2006 has been approved by CEN as EN ISO 19458:2006 without any modifications. EN ISO 19458:2006Reference numberISO 19458:2006(E)

14、INTERNATIONAL STANDARD ISO19458First edition2006-08-01Water quality Sampling for microbiological analysis Qualit de leau chantillonnage pour analyse microbiologique EN ISO 19458:2006ii iiiContents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Sampling point 1 4 Sampling te

15、chnique 2 5 Transport and storage 10 Annex A (informative) A priori determination of the number of samples to analyse to determine the mean concentration of microbes in water with a given confidence, for quantitative determination derived by cultivation of microorganisms 13 Annex B (informative) Rec

16、ommended (R) and acceptable (A) values for maximum sample storage times including transport time and temperatures unless otherwise specified in specific standards. 16 Bibliography . 17 EN ISO 19458:2006iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of

17、national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. Inte

18、rnational organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with th

19、e rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval b

20、y at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 19458 was prepared by Technical Committee IS

21、O/TC 147, Water quality, Subcommittee SC 4, Microbiological methods. EN ISO 19458:2006vIntroduction Appropriate sampling is essential to provide representative samples to the laboratory in charge of testing. Sampling features depend on the objective of sampling, but also on the nature of the sample.

22、 Microorganisms are living organisms. In addition, when they are introduced into water, they do not form a perfect solution, but a suspension with an inherent degree of variability. Sampling objectives may serve different purposes, which are described in the ISO 5667 series of standards (ISO 5667-1,

23、 ISO 5667-2 and ISO 5667-3): a) determination of the compliance of a water with a regulatory quality specification; b) characterization of any contamination, its level (mean) and its variations: 1) what is its random variation? 2) is there a trend? 3) are there cycles? c) identification of the sourc

24、es of pollution. Regarding the number or frequency of samples, it will vary according to the aim of the sampling. The minimum number of samples will be low if the mean concentration differs greatly from the specification (much lower or much higher), and the minimum number of samples will be higher i

25、f the mean concentration and the specification are close to one another. Similarly, in case b), when looking for a trend: the less obvious the trend, the higher the frequency of sampling (see also Annex A). EN ISO 19458:2006blank1Water quality Sampling for microbiological analysis WARNING Persons us

26、ing this International Standard should be familiar with normal laboratory practice. This standard 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 appropriate safety and health practices and to ensure complianc

27、e with any national regulatory conditions. IMPORTANT It is absolutely essential that tests conducted according to this standard be carried out by suitably trained staff. 1 Scope This International Standard provides guidance on planning water sampling regimes, on sampling procedures for microbiologic

28、al analysis and on transport, handling and storage of samples until analysis begins. It focuses on sampling for microbiological investigations. General information in respect to the sampling from distinct water bodies is given in the respective parts of ISO 5667. 2 Normative references The following

29、 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 referenced document (including any amendments) applies. ISO 5667-1, Water quality Sampling Part 1: Guidance on the des

30、ign of sampling programmes and sampling techniques ISO 5667-2, Water quality Sampling Part 2: Guidance on sampling techniques ISO 5667-3, Water quality Sampling Part 3: Guidance on the preservation and handling of water samples 3 Sampling point The sampling site shall provide representative characte

31、ristics and account for any vertical, horizontal and temporal variations and shall be identified precisely following the general recommendations of ISO 5667-1 and ISO 5667-2, taking into account additional aspects specific to microbiology. Sampling points where conditions are unstable should be avoi

32、ded, and the heterogeneity of the hydraulic system shall be taken into consideration. In studies on the efficacy of disinfection, the sampling point shall be chosen to ensure that the reaction is complete. EXAMPLE Examples of how the heterogeneity of the system may influence the results are given be

33、low. It is not equivalent to take a subsurface or a surface sample, or a subsurface sample “contaminated” during recovery through the surface film. In some instances (e.g. lakes, swimming pools), the concentration in the surface film can be 1 000 times higher than in the subsurface. EN ISO 19458:200

34、62 All the points of a network are not equivalent, as there may be dead ends and sections where the flow is reduced, particularly if the network is fed from two sources. The quality at the outlet of a well-mixed tank is generally the same as in the body of water, but can be quite different from the

35、inlet. 4 Sampling technique 4.1 Personnel Formal training, training records and determination of competence shall be described for all those who sample, and this information shall be properly documented. 4.2 Sample containers 4.2.1 General For routine samples (for example, sampling at taps, recreati

36、onal waters, swimming pool waters), use clean, sterile bottles. The volume of the bottles should be adequate for analysis of all requested parameters. For sampling by immersion in clean waters, use bottles that are sterile both inside and out and protected, for example, by kraft paper (to keep dry a

37、fter autoclaving), aluminium foil or by plastic outer bags. If not autoclavable, sterilization with gamma rays or by ethylene oxide may be used. The bag can then be opened just before sampling and can also serve as a glove to hold the bottle to provide maximum asepsis before being placed on a pole o

38、r other sterilizable sampling apparatus. Alternatively, the outside of sample bottles may be disinfected immediately prior to immersion by a suitable disinfectant such as isopropanol (4.3.1.1) and allowed to dry before use. This is not suitable for analysis of spore-forming bacteria. In most cases,

39、500 ml bottles are sufficient, as less than five categories of microorganisms are measured, each involving inoculation of a maximum of 100 ml. In some cases, larger volumes are necessary, e.g.: for bottled water analysis (250 ml per parameter); for Legionella spp. or Salmonella spp. (up to 1 l); for

40、 viruses, Giardia cysts, Cryptosporidium oocysts, amoebae in clean waters, from 10 to several hundred litres or more are examined. Usually, a concentration step is made on site using a cartridge filter which is then transported to the laboratory. Bottles can be made of glass or various plastics (pol

41、ypropylene, polystyrene, polyethylene, polycarbonate). Usually glass is preferred for re-use, and polyethylene is used as disposable. Adhesion to surfaces can lower the detection of microorganisms, and the critical tangential surface tension has to be considered if a non-standard material is used13.

42、 Closures can be a ground glass or plastic stopper for glass bottles, a plastic press-on lid for plastic bottles or jars, or a plastic or metal screw cap for either. Bottle openings closed with plastic or glass stoppers should be further protected from contamination by, e.g. aluminium foil. When lar

43、ger volumes are necessary for the assay of, for example, viruses, Salmonella spp., amoebae, Cryptosporidium oocysts, Giardia cysts, it is sometimes necessary to analyse tens of litres or hundreds of EN ISO 19458:20063litres. To avoid the difficulties of handling, refrigerating and agitating such vol

44、umes, a concentration step in situ (by flocculation, centrifugation or filtration) is recommended. Peristaltic pumps can be used with sterile tubing. NOTE 1 Metal caps, especially aluminium, can produce toxicity when autoclaved. This can be prevented by incorporating a heat-resistant leak-proof line

45、r. NOTE 2 Certain materials can also give toxic by-products when heat sterilized, even in a dry oven, or induce pH changes. NOTE 3 Some brands of cotton wool used to make plugs for glassware may become toxic if they are heated for too long at too high temperatures. NOTE 4 Press-on plastic lids attac

46、hed to the bottle or jar have several advantages in that they are as leak-proof as screw-caps, and the lids can stand open, which facilitates filling and pipetting. When open, the lid remains linked to the bottle, so bottles and closures are kept together, and the lid is also protected from contamin

47、ation. 4.2.2 Sterilization of bottles If re-used, clean glass bottles and their closures with a non-toxic, phosphorus-free detergent, followed by a thorough rinse with deionized or distilled water. Autoclave bottles at (121 3) C for at least 15 min. Keep the closure of the bottles loose, to allow th

48、e steam to replace all the air during the temperature rise, and to prevent plastic bottles from collapsing when cooling. Tighten screw caps after sterilization. Autoclave glass stoppers separately from the bottle, or use a paper or aluminium separator to prevent the stopper sticking on cooling. If n

49、ecessary, sterilize bottles in a dry oven for at least 1 h at (170 10) C. Separate ground glass stoppers from the neck by a paper strip or a piece of string to avoid jamming during cooling. The bottles should be traceable to the sterilization date. Control the effectiveness of the sterilization process by chemical or biological indicators. When sterilization is not possible with any other means, disinfect by immersing open bottles in boiling water for at least 30 min. Immediately after boiling, empty the bottles and close them with