1、BRITISH STANDARD BS ISO 12771:1997 Plastics Laboratory Ware Disposable serological pipettes ICS 11.100; 71.040.20BSISO12771:1997 This British Standard, having been prepared under the directionof the Sector Board forMaterials and Chemicals, waspublished under the authorityof the Standards Boardand co
2、mes into effect on 15 September 1997 BSI 09-1999 ISBN 0 580 28410 7 National foreword This British Standard reproduces verbatim ISO 12771:1997 and implements it as the UK national standard. The UK participation in its preparation was entrusted by Technical Committee LBI/36, Laboratory glassware and
3、related apparatus, to Subcommittee LBI/36/1, Volumetric instruments, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; mo
4、nitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this
5、 document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of
6、 British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the ISO title page, pages ii to iv, pages 1 t
7、o 4 and abackcover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSISO12771:1997 BSI 09-1999 i Contents Page National fo
8、reword Inside front cover Foreword iii Text of ISO 12771 1ii blankBSISO12771:1997 ii BSI 09-1999 Contents Page Foreword iii 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Basis of adjustment 1 5 Dimensions and delivery times 1 6 Construction 1 7 Volumetric performance 2 8 Definition of capacit
9、y 2 9 Determination of accuracy and repeatability 3 10 Marking 3 Annex A (informative) Bibliography 4 Table 1 Capacity, subdivision, dimensions and delivery times 2 Table 2 Dimensions of optional suction tubes 2 Descriptors: Laboratory equipment, disposable equipment, plastics products, pipettes, sp
10、ecifications, dimensions, capacity, marking, colour codes.BSISO12771:1997 BSI 09-1999 iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried ou
11、t 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-governmental, in liaison with ISO, also take part in the work. ISO co
12、llaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval
13、 by at least75% of the member bodies casting a vote. International Standard ISO12771 was prepared by Technical Committee ISO/TC48, Laboratory glassware and related apparatus, Subcommittee SC1, Volumetric instruments. Annex A of this International Standard is for information only.iv blankBSISO12771:1
14、997 BSI 09-1999 1 1 Scope This International Standard specifies requirements for disposable plastics serological pipettes, gauged to deliver, suitable for general laboratory purposes. 2 Normative references The following standards contain provisions which, through references in this text, constitute
15、 provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the s
16、tandards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 1043-1:1987, Plastics Symbols Part1:Basic polymers and their special characteristics. ISO 1769:1975, Laboratory glassware Pipettes Colour coding. ISO 8417:, Laboratory volumetric instr
17、uments Principles of design and construction of disposable volumetric articles 1) . 3 Definitions For the purposes of this International Standard, the following definitions apply. 3.1 disposable adjective used to describe serological pipettes which are intended to be used once only and then discarde
18、d NOTESuch pipettes will only be expected to provide their specified performance during the original operation. 3.2 accuracy (of a pipette) closeness of agreement between the nominal volume and the true volume, obtained by applying the test procedure specified in clause9.1. It is quantified by the c
19、apacity deviation 3.3 repeatability (of a number of pipettes) closeness of agreement between the individual volumes obtained by applying the test procedure specified in9.2 NOTE 1Definitions and terms are in agreement with the “International Vocabulary of Basic and General Terms in Metrology”. See IS
20、O3534-1 for details. NOTE 2The definitions for accuracy and repeatability apply only in cases where the distributions are Gaussian. 4 Basis of adjustment 4.1 Unit of volume The unit of volume is the cubic centimetre (cm 3 ), for which the name millilitre (ml) may be used. NOTEThe term millilitre (ml
21、) is commonly used as a special name for the cubic centimetre (cm 3 ), in accordance with the International System of Units (SI). 4.2 Reference temperature The reference temperature, i.e.the temperature at which the pipette is intended to deliver its nominal volume (nominal capacity), is20 C. When t
22、he pipette is required for use in a country which has adopted a reference temperature of27 C (the alternative specified in ISO8417 for tropicaluse), this figure shall be substituted for20 C. 4.3 Adjustment The pipettes shall be adjusted to deliver the required volume (i.e.the nominal volume or a par
23、tof it) with the last drop to be blown out. 5 Dimensions and delivery times The dimensions and delivery times shall be as shown in Table 1. The delivery time shall be determined with the pipette unplugged, and with distilled water at a temperature of20 C. 6 Construction 6.1 Material The pipettes sha
24、ll be made of translucent plastics material of chemical and physical properties suitable for their intended use. The plastic material or its symbol in accordance with ISO1043-1 shall be marked on each pipettes. 6.2 Graduation and figuring The pipettes shall be provided with a graduation in accordanc
25、e with ISO8417, and figured accordingly. Graduation and figuring shall be durable until the pipette has been used. The pipettes shall be graduated from0at the top down to the lowest graduation line according to Table 1. The distance between the top of the pipette and the zero line shall be at least9
26、0mm for pipettes with a separate suction tube and75mm minimum for pipettes without suction tube. 1) To be published.BSISO12771:1997 2 BSI 09-1999 Table 1 Capacity, subdivision, dimensions and delivery times 6.3 Design 6.3.1 Pipettes shall be straight. Any cross-section of a pipette taken in a plane
27、perpendicular to the longitudinal axis shall be reasonably circular. 6.3.2 The lower end of the pipette shall terminate in a delivery jet having a smooth and gradual taper of10mm to65mm without any sudden constriction at the orifice which could give rise to turbulent outflow. The end of the jet shal
28、l be reasonably perpendicular to the longitudinal axis of the pipette. 6.3.3 The suction end shall be perpendicular to the longitudinal axis of the pipette. If a suction tube is provided on the5ml and10ml sizes, its dimensions shall be as given in Table 2. Table 2 Dimensions of optional suction tube
29、s The diameter is measured at the open end of the mouthpiece. 6.4 Workmanship The pipettes shall be free from defects that may impair their serviceability, such as foreign matter or chips that affect the bore. 6.5 Colour code The pipettes may be colour coded to indicate their nominal capacity. If th
30、ey are colour coded, the code shall be in accordance with ISO1769. 7 Volumetric performance When tested in accordance with clause9, the accuracy and repeatability shall be within the limits stated by the manufacturer. 8 Definition of capacity 8.1 Setting of the meniscus 8.1.1 The meniscus shall be s
31、et so that the plane of the upper edge of the graduation line is horizontally tangential to the lowest point of the meniscus, the line of sight being in the same plane. 8.1.2 In order that the lowest point of the meniscus may be observed, a shade of some dark material should be placed immediately be
32、low and behind the meniscus, which renders the profile of the meniscus dark and clearly visible against a light background. 8.2 Capacity The capacity corresponding to any graduation line is defined as the volume of water at20 C, expressed in millilitres, delivered by the pipette at20 C, when emptied
33、 from the graduation line to the jet, outflow being unrestricted until it is sure that the meniscus has come to rest in the jet, but with delivery being completed by expelling the last drop by blowing. NOTEIt should be borne in mind that the delivered volume is the complement of the indicated volume
34、 to the total volume, e.g.if the indication on a10ml pipette is4ml, the delivered volume is6ml. Where, exceptionally, the reference temperature is27 C, this value shall be substituted for20 C. The clean pipette shall be held in a vertical position and filled with distilled water to a few millimetres
35、 above the graduation line; the falling meniscus shall then be set to the 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 slightly inclined so that
36、 the tip of the jet is in contact with the inside of the vessel, but without movement of one against the other throughout the delivery period. Nominal capacity Smallest scale division Lowest graduation line at External diameter Wall thickness min. Delivery times min. max. ml ml ml mm mm s 0,5 0,01 0
37、,4 4,5 to 4,8 0,8 0,5 3,0 1 0,01 0,9 4,5 to 5,0 0,8 0,5 3,0 1 0,1 0,9 4,5 to 5,0 0,8 0,5 3,0 2 0,01 1,8 5,4 to 6,7 0,9 0,5 4,0 2 0,1 1,8 5,4 to 6,7 0,9 0,5 4,0 5 0,1 4,0 7,6 to 10,0 0,9 0,5 7,0 10 0,1 9,0 9,5 to 11,7 0,9 0,5 8,0 Length Diameter internal external mm mm mm 20 to 28 2 to 6 6 to 9BSISO1
38、2771:1997 BSI 09-1999 3 To ensure that delivery is complete, a waiting time of approximately3s should be observed before expelling the last drop by blowing and removing the pipette from the receiving vessel. NOTEThe waiting period of3s is specified only for the purpose of definition. In use, it is n
39、ot necessary to adhere closely to this period; it is sufficient to be certain that the meniscus has come to rest in the jet before blowing out the pipette. 9 Determination of accuracy and repeatability Volumetric accuracy and repeatability shall be determined for a single pipette or a minimum of30pi
40、pettes as specified in9.1 or9.2. 9.1 Volumetric capacity deviation (single pipette) Accuracy for a single pipette shall be calculated as follows: Capacity deviation% = where 9.2 Volumetric capacity deviation (number of pipettes) Repeatability for a minimum of30pipettes shall be calculated as follows
41、: Repeatability% = where Coefficient of variation: CV% = where 10 Marking 10.1 The following inscriptions shall be marked on each pipette: a) the nominal capacity; b) the symbol “ml” or the symbol “cm 3 ” to indicate the unit in terms of which the pipette is graduated; c) the inscription “20 C” to i
42、ndicate the reference temperature; where, exceptionally, the reference temperature is27 C, this value shall be substituted for20 C; d) the letters “Ex” to indicate that the pipette has been constructed to deliver its indicated capacity; e) the makers or vendors name or mark; f) a wide band or two na
43、rrow bands on the pipette top to signify that the last drop must be blown out to achieve full delivery; g) the plastic material or its symbol in accordance with ISO1043-1. Alternatively this information may be given on the smallest packaging unit (see10.2) or in the user information. 10.2 The smalle
44、st packaging unit of pipettes shall be clearly marked with the following information: a) manufacturers name and/or mark; b) product description, e.g.disposable serological pipette,5ml; c) volumetric performance in terms of accuracy and repeatability; d) number of pipettes in the box; e) batch number
45、 or date of manufacture; f) the number of this International Standard; g) the type of plastic material from which the pipettes are manufactured, including its symbol in accordance with ISO1043-1. V 1 is the capacity at the reference temperature; V 0 is the nominal capacity of the pipette. is the mea
46、n of the sample measurements at the reference temperature; V 0 is the nominal capacity of the pipettes. V 1 is the individual sample measurement at the reference temperature; is the mean of the sample measurements; n is the number of pipettes measured. 100 V 1 V 0 () V 0 - 100 VV 0 () V 0 - V 100s V
47、 - VBSISO12771:1997 4 BSI 09-1999 Annex A (informative) Bibliography 1 ISO 3534-1:1993, Statistics Vocabulary and symbols Part 1: Probability and general statistical terms. 2 VIM:1993, International Vocabulary of Basic and General Terms in Metrology.5 blankBS ISO 12771:1997 BSI 389 Chiswick High Roa
48、d London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or r
49、evision. Users of BritishStandards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this BritishStandard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel:02089969000. Fax:020899
