1、BRITISH STANDARDBS EN ISO 835:2007Laboratory glassware Graduated pipettesThe European Standard EN ISO 835:2007 has the status of a British StandardICS 17.060g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55
2、g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 835:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2007 BSI 2007ISBN 978 0 580 50762 5National forewordThis British Standard was published by BSI. It is the UK imp
3、lementation of EN ISO 835:2007. It supersedes BS 700-1:1982, BS 700-2:1982 and BS 700-3:1982, which are withdrawn.The UK participation in its preparation was entrusted by Technical Committee LBI/36, Laboratory glassware and related apparatus, to Subcommittee LBI/36/1, General and volumetric, glass a
4、nd plastics apparatus.A list of organizations represented on this committee can be obtained on request to its secretary.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 cannot
5、 confer immunity from legal obligations.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 835April 2007ICS 17.060English VersionLaboratory glassware - Graduated pipettes (ISO 835:2007)Verrerie de laboratoire - Pipettes gradues (ISO 835:200
6、7) Laborgerte aus Glas - Messpipetten (ISO 835:2007)This European Standard was approved by CEN on 13 March 2007.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 alte
7、ration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management 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 trans
8、lationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, G
9、reece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement
10、 Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 835:2007: EForeword This document (EN ISO 835:2007) has been prepared by Technical Committee ISO/TC 48 “Laboratory glassware and re
11、lated apparatus“ in collaboration with Technical Committee CEN/TC 332 “Laboratory equipment“, 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 October 2007,
12、 and conflicting national standards shall be withdrawn at the latest by October 2007. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic,
13、Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 835:2007 has been approved
14、 by CEN as EN ISO 835:2007 without any modifications. EN ISO 835:2007Reference numberISO 835:2007(E)INTERNATIONAL STANDARD ISO835First edition2007-04-01Laboratory glassware Graduated pipettes Verrerie de laboratoire Pipettes gradues EN ISO 835:2007ii iiiContents Page Foreword iv 1 Scope . 1 2 Normat
15、ive references . 1 3 Terms and definitions. 1 4 Basis of adjustment 2 4.1 Unit of volume. 2 4.2 Delivery volume 2 4.3 Reference temperature. 2 5 Types and classes of accuracy. 2 5.1 Classes of accuracy . 2 5.2 Types of pipettes 2 6 Maximum permissible errors. 3 7 Construction 4 7.1 Material 4 7.2 Di
16、mensions 4 7.3 Top of pipette 4 7.4 Delivery jet. 4 7.5 Delivery time 5 7.6 Waiting time. 5 8 Graduation, figuring and patterns. 5 8.1 Graduation patterns 5 8.2 Position of graduation lines 5 8.3 Figuring of graduation lines 5 9 Setting of the meniscus . 6 10 Marking 6 11 Visibility of graduation li
17、nes, figures and inscriptions. 7 12 Colour coding 7 Annex A (normative) Definition of capacities and delivery times. 8 Bibliography . 12 EN ISO 835:2007iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The
18、 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. International organizations, governmental and non-gove
19、rnmental, 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 the rules given in the ISO/IEC Directives, Part 2. T
20、he 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 by at least 75 % of the member bodies casting a vot
21、e. 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 835 was prepared by Technical Committee ISO/TC 48, Laboratory equipment, Subcommittee SC 6, La
22、boratory and volumetric ware. This first edition of ISO 835 cancels and replaces ISO 835-1:1981, ISO 835-2:1981, ISO 835-3:1981 and ISO 835-4:1981, which have been technically revised and combined into one document. EN ISO 835:20071Laboratory glassware Graduated pipettes 1 Scope This International S
23、tandard specifies metrological and constructional requirements for graduated pipettes, adequate for general laboratory purposes. The details specified are in conformity with the principles of design and construction of volumetric glassware given in ISO 384. NOTE For one-mark pipettes, see ISO 648. F
24、or piston-operated pipettes, see ISO 8655-2. 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 referenced document (including any am
25、endments) applies. ISO 384:1978, Laboratory glassware Principles of design and construction of volumetric glassware ISO 719, Glass Hydrolytic resistance of glass grains at 98 C Method of test and classification ISO 1769, Laboratory glassware Pipettes Colour coding ISO 3696, Water for analytical labo
26、ratory use Specification and test methods 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 delivery volume volume of liquid discharged from the pipette NOTE Due to retention of liquid on the inner surface of the pipette, the volume of liquid d
27、elivered is not identical with the volume of liquid contained by the pipette. 3.2 delivery time time required for the pipette to deliver its nominal volume 3.3 waiting time time to be observed after apparent completion of the liquid delivery of the pipette and before the final reading of the deliver
28、ed volume is taken NOTE A waiting time applies for graduated pipettes of Class AS (see 5.1 and 7.6). EN ISO 835:20072 4 Basis of adjustment 4.1 Unit of volume The unit of volume shall be the millilitre (ml) which is equivalent to the cubic centimetre (cm3). 4.2 Delivery volume Graduated pipettes sha
29、ll be adjusted with water according to ISO 3696, grade 3, to deliver their specified volume (Ex). The delivery should be under gravity and unrestricted. For details, see 7.5. 4.3 Reference temperature The standard reference temperature, i.e. the temperature at which the pipette is intended to delive
30、r its volume, shall be 20 C. When the pipette is required for use in a country which has adopted a standard reference temperature of 27 C (the alternative recommended in ISO 384 for tropical use), this figure shall be substituted for 20 C. 5 Types and classes of accuracy 5.1 Classes of accuracy Two
31、classes of accuracy are specified: Classes A and AS for the higher grade; Class B for the lower grade. The maximum permissible errors for both classes are specified in Table 1. The pipettes shall be adjusted as follows: Class A: without waiting time; Class AS: with a specified waiting time of 5 s (s
32、ee 7.6); Class B: without waiting time. 5.2 Types of pipettes 5.2.1 Type 1: Partial delivery Graduated pipettes adjusted for delivery of a liquid from zero line at the top to any graduation line; nominal capacity shall be represented by the lowest graduation line. 5.2.2 Type 2: Total delivery Gradua
33、ted pipettes adjusted for delivery of a liquid from any graduation line down to the jet; nominal capacity shall be represented by the highest graduation line. EN ISO 835:200735.2.3 Type 3: Total delivery Graduated pipettes adjusted for delivery of a liquid from zero line at the top to any graduation
34、 line; nominal capacity shall be obtained by delivery down to the jet. 5.2.4 Type 4: Blow-out Graduated pipettes for total delivery (see Type 3) where the last drop of liquid in the jet is expelled by blowing. Blow-out pipettes shall be adjusted to accuracy Class B. 6 Maximum permissible errors Maxi
35、mum permissible errors in the delivered volume shall not exceed the limits specified in Table 1. These limits represent the maximum permitted error at any point and also the maximum permissible difference between the errors at any two points. Table 1 Capacities, subdivisions and maximum permissible
36、errors Nominal capacity Smallest scale division Maximum permissible error ml ml Classes A and AS ml Class B ml 0,1 0,01 0,006 0,01 0,2 0,01 0,006 0,01 0,5 0,01 0,006 0,01 1 0,01 0,007 0,01 1 0,10 0,007 0,01 2 0,02 0,010 0,02 2 0,10 0,010 0,02 5 0,05 0,030 0,05 5 0,10 0,030 0,05 10 0,1 0,05 0,1 20 0,
37、1 0,1 0,2 25 a0,1 0,1 0,2 25 0,2 0,1 0,2 aLength 450 mm, see Table 2. If graduated pipettes are required of capacities and/or subdivisions other than those listed in Table 1, they shall conform to the essential requirements of this International Standard. The relationships between maximum permissibl
38、e error and capacity, as well as between maximum permissible error and meniscus diameter as given in ISO 384:1978, Annex A and Annex B, shall be observed. EN ISO 835:20074 7 Construction 7.1 Material Graduated pipettes shall be manufactured from glass of chemical resistance and thermal properties wh
39、ich are at least to class HGB3 in accordance with ISO 719, and shall be as free as possible from visible defects and shall be reasonably free from internal stress. 7.2 Dimensions Graduated pipettes shall comply with the essential dimensional requirements shown in Table 2. Table 2 Dimensions Nominal
40、capacity ml Dimensions mm 0,1 0,2 0,5 1 2 5 10 20 25 25 Smallest scale division ml 0,01 0,01 0,01 0,010,100,020,100,050,100,1 0,1 0,1 0,2 Essential dimensions Distance from zero line to lowest graduation line for Type 1 pipettes min. max. 80170 120200 130220 160 220 160 220 140220 140 220 140 220 22
41、0 290 180220 Distance from highest to lowest figured graduation lines for Types 2, 3 and 4 pipettes min. max. 70160 110190 110 220 140 220 140 220 140220 140 220 140 220 200 290 160 220 Distance from highest graduation line to top of pipette min. 100 External diameter of suction tube approx. 5,25 to
42、 9 5,5 to 9 Length of tube of uniform bore below lowest graduation line min. 5 Recommended dimensions Overall length approx. 300 340 360 360 360 360 360 360 450 360 Length of tapered portion forming jet approx. 15 15 20 20 20 25 25 30 30 30 Wall thickness approx. 2 2 2 2 1,5 1 1 1 1 1 7.3 Top of pip
43、ette The top of the graduated pipette shall lie in a plane at right angles to the axis of the pipette and shall be free from any blemishes which might interfere with the required accurate control by a mechanical device or by the finger, in setting the meniscus. The end may be lightly fire-polished o
44、r smoothly ground with a slight bevel on the outside. The upper end of the pipette tube may be made from tubing of uniform bore or may have a constriction at about 25 mm below the top to enable the retention of a porous, air-permeable plug, such as a cotton plug. 7.4 Delivery jet The lower end of th
45、e graduated pipette shall terminate either in a delivery jet having a smooth and gradual taper or in a capillary end, both without sudden constriction at the orifice which could give rise to turbulent outflow. The end of the jet may be finished by grinding or machine tooling and may be fire polished
46、. EN ISO 835:200757.5 Delivery time The delivery time is defined as the time occupied by the free descent of the water meniscus (delivery under gravity) from the highest graduation line: to the lowest graduation line, in the case of Type 1 graduated pipettes; to the point at which the meniscus appea
47、rs to come to rest in the jet, in the case of Type 2, Type 3 and Type 4 graduated pipettes. For testing of the delivery time, the clean graduated pipette shall be held in a vertical position, if appropriate with no porous, air-permeable plug fitted, and filled with water to a few millimetres above t
48、he uppermost graduation line; the falling meniscus shall then be set to this line. Any drop adhering to the jet of the pipette shall be removed by touching the tip of the jet against the inner surface of an inclined glass vessel. Delivery shall then be made into another glass vessel (the receiving v
49、essel), so that the tip of the jet is in contact with the inner surface of this receiving vessel, above the level of any collected liquid, but without movement of one against the other throughout the delivery period. IMPORTANT It is important that a glass receiving vessel is used. Capillary effects influencing the delivery time depend considerably on the material on which the liquid runs down. The delivery time thus determined shall be within the limits specified for the particular pipette (see Annex A). In the case of Type 4 (blow-ou
