1、BS EN ISO648:2008ICS 17.060NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDLaboratory glassware Single-volumepipettes (ISO 648:2008)This British Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 31 October2008 BSI 2008ISBN
2、978 0 580 58559 3Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 648:2008National forewordThis British Standard is the UK implementation of EN ISO 648:2008. Itsupersedes BS1583:1986 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee LB
3、I/36/1, General and volumetric, glass and plasticsapparatus.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application.Compl
4、iance with a British Standard cannot confer immunityfrom legal obligations.EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 648October 2008ICS 17.060English VersionLaboratory glassware - Single-volume pipettes (ISO 648:2008)Verrerie de laboratoire - Pipettes un volume (ISO648:2008)Laborgerte au
5、s Glas - Vollpipetten (ISO 648:2008)This European Standard was approved by CEN on 4 October 2008.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-d
6、ate 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 translationunder the
7、 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, Greece, Hungary,
8、 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 Centre: rue de
9、 Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 648:2008: EBS EN ISO 648:2008EN ISO 648:2008 (E) 3 Foreword This document (EN ISO 648:2008) has been prepared by Technical Committee ISO/TC 48 “La
10、boratory glassware and related 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 th
11、e latest by April 2009, and conflicting national standards shall be withdrawn at the latest by April 2009. Attention is drawn to the possibility 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
12、 such patent rights. 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, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Icel
13、and, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 648:2008 has been approved by CEN as a EN ISO 648:2008 without any modification. BS EN
14、ISO 648:2008ISO 648:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv 1 Scope . 1 2 Normative 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 a
15、ccuracy . 2 5.2 Types of single-volume pipette . 2 6 Maximum permissible errors. 3 7 Construction 3 7.1 Material 3 7.2 Shape . 3 7.3 Bulb 3 7.4 Dimensions 4 7.5 Top of pipette 5 7.6 Delivery jet. 5 7.7 Delivery time 5 7.8 Waiting time. 6 8 Graduation line(s) . 6 9 Setting of the meniscus . 6 10 Mark
16、ing 6 11 Visibility of graduation lines, figures and inscriptions. 7 12 Colour coding 7 Bibliography . 8 BS EN ISO 648:2008ISO 648:2008(E) iv ISO 2008 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO memb
17、er 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. International organizations, government
18、al 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 the rules given in the ISO/IEC Direct
19、ives, 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 by at least 75 % of the member bodie
20、s 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 648 was prepared by Technical Committee ISO/TC 48, Laboratory equipment, Subcom
21、mittee SC 6, Laboratory and volumetric ware. This second edition cancels and replaces the first edition (ISO 648:1977), which has been technically revised to incorporate the following modifications: a) single-volume pipettes with two marks have been added; b) the waiting time for pipettes Class AS h
22、as been reduced to 5 s; c) dimensions have been modified; d) the nominal volume of 200 ml has been deleted. BS EN ISO 648:2008INTERNATIONAL STANDARD ISO 648:2008(E) ISO 2008 All rights reserved 1Laboratory glassware Single-volume pipettes 1 Scope This International Standard specifies metrological an
23、d constructional requirements for volumetric pipettes with one mark (total delivery) and for volumetric pipettes with two marks, both of which are adequate for general laboratory purposes. The details specified are in conformity with the principles of design and construction of volumetric glassware
24、given in ISO 384. NOTE For graduated pipettes, see ISO 835. For 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, th
25、e latest edition of the referenced document (including any amendments) 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 glasswa
26、re Pipettes Colour coding ISO 3696, Water for analytical laboratory 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 liqui
27、d on the inner surface of the volumetric instrument, the volume of liquid delivered is not identical with the volume of liquid contained by the volumetric instrument. 3.2 delivery time time required for the descent of the liquid meniscus from the graduation line to the point at which the meniscus ap
28、pears to come to rest in the jet for one-mark pipettes and from the upper graduation line to the lower graduation line for two-mark pipettes 3.3 waiting time time to be observed after apparent completion of the liquid delivery of the volumetric instrument NOTE A waiting time applies for Class AS sin
29、gle-volume pipettes (see Clause 5 and 7.8). BS EN ISO 648:2008ISO 648:2008(E) 2 ISO 2008 All rights reserved4 Basis of adjustment 4.1 Unit of volume The unit of volume shall be the millilitre (ml), which is equivalent to one cubic centimetre (cm3). 4.2 Delivery volume Single-volume pipettes shall be
30、 adjusted with water of grade 3 quality, in accordance with to ISO 3696, to deliver their nominal volume (Ex). The delivery should be under gravity and unrestricted. For details, see 7.7 and 7.8. 4.3 Reference temperature The standard reference temperature, i.e. the temperature at which the pipette
31、is intended to deliver its nominal 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
32、 5.1 Classes of accuracy Two classes of accuracy are specified: Class A and AS for the higher grade; Class B for the lower grade. 5.2 Types of single-volume pipette The following two types of single-volume pipettes are specified: those for which no waiting time is specified (Classes A and B); those
33、for which a waiting time of 5 s is specified (Class AS). BS EN ISO 648:2008ISO 648:2008(E) ISO 2008 All rights reserved 36 Maximum permissible errors Maximum permissible errors in the delivered volume shall not exceed the limits specified in Table 1. Table 1 Nominal volumes and maximum permissible e
34、rrors Maximum permissible error Nominal volume Class A and AS Class B ml ml ml 0,5 0,005 0,010 1 0,008 0,015 2 0,010 0,02 5 0,015 0,03 10 0,02 0,04 20 0,03 0,06 25 0,03 0,06 50 0,05 0,10 100 0,08 0,15 The relationships between maximum permissible error and nominal volume, as well as between maximum
35、permissible error and meniscus diameter as given in ISO 384:1978, Annex A and Annex B, shall be observed. For the maximum permissible errors of single-volume pipettes with intermediate nominal volumes between those given in Table 1, the value for the nearest nominal volume shall apply. If the interm
36、ediate volume is exactly halfway between those given in Table 1, the value for the next greater nominal volume shall apply. 7 Construction 7.1 Material Single-volume pipettes shall be manufactured from glass of chemical resistance and thermal properties at least to HGB3 in accordance with ISO 719, s
37、hall be as free as possible from visible defects and reasonably free from internal stress. 7.2 Shape Pipettes of 0,5 ml nominal volume shall consist of a straight tube with a jet at the lower end. Pipettes of nominal volume 1 ml and 2 ml may be of similar straight tube pattern or may alternatively b
38、e of bulb pattern, as described herein for the larger sizes. All larger pipettes shall consist of a bulb with suction and delivery tubes, the three portions being straight and coaxial. 7.3 Bulb The main portion of the bulb shall be cylindrical, except that 1 ml and 2 ml nominal-volume pipettes may h
39、ave an oval bulb if desired. The two ends of the bulb shall merge gradually into the suction and delivery tubes, the junctions being of tapered formation to facilitate drainage. BS EN ISO 648:2008ISO 648:2008(E) 4 ISO 2008 All rights reserved7.4 Dimensions Single-volume pipettes shall comply with th
40、e dimensional requirements shown in Tables 2, 3 and 4. Table 2 Dimensions Nominal volume ml Dimensions mm 0,5 1 2 5 10 20 25 50 100 Overall length max. 300 325 350 410 450 520 530 550 600 Internal diameter at the graduation line max. 2,5 3,5 4,5 4,5 5 5,5 5,5 6 7,5 Length of suction tube valid only
41、for bulb pattern pipettes min. 150 150 150 160 170 170 170 170 Length of delivery tube valid only for bulb pattern pipettes min. 110 125 145 160 210 220 230 240 External diameter of delivery tube valid only for bulb pattern pipettes 1 5 6 6,5 7 7 7 8 9 External diameter of bulb valid only for bulb p
42、attern pipettes max. 9 9 12 16 22 24 30 38 External diameter of tube valid only for straight pattern pipettes max. 5 6 7 Table 3 Dimensions applying to all nominal volumes of one-mark pipettes Dimension Size mm Distance of graduation line from top of pipette min. 100 Distance from graduation line to
43、 top of bulba min. 10 Distance from graduation line to tip of jet valid only for straight pattern pipettes min. 110 Wall thickness bulb pattern pipettes straight pattern pipettes min. min. 0,6 0,8 aTop of bulb relates to the point at which the suction tube begins to expand into the bulb.BS EN ISO 64
44、8:2008ISO 648:2008(E) ISO 2008 All rights reserved 5Table 4 Dimensions applying to all nominal volumes of two-mark pipettes Dimension Size mm Distance of upper graduation line from top of pipette min. 100 Distance from upper graduation line to top of bulba min. 10 Distance from upper graduation line
45、 to tip of jet valid only for straight pattern pipettes min. 110 Distance from lower graduation line to bottom of bulba min. 20 Distance from lower graduation line to tip of jet min. 30 Wall thickness bulb pattern pipettes straight pattern pipettes min. min. 0,6 0,8 aTop of bulb and bottom of bulb r
46、elate to the points at which the suction tube and the delivery tube begin to expand into the bulb.7.5 Top of pipette The top of the single-volume 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 accur
47、ate control by a mechanical device or by the finger in setting the meniscus. The end may be lightly fire-polished or smoothly ground with a slight bevel on the outside. 7.6 Delivery jet The lower end of the pipette shall terminate either in a delivery jet having a smooth and gradual taper or in a ca
48、pillary 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. 7.7 Delivery time For testing of the delivery time, the clean pipette shall be held in a vertical posit
49、ion and filled with de-ionized water to a few millimetres above the (upper) 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 bringing the surface of a glass vessel into contact with the tip of the jet. Delivery shall then be made into another glass vessel which is slightly inclined so that the tip of the jet is in contact with the inside of the vessel, but without movement of one against t
