1、Designation: E714 94 (Reapproved 2009)Standard Specification forDisposable Glass Serological Pipets1This standard is issued under the fixed designation E714; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers disposable glass serologicalpipets, calibrated “to deliver,” used in measuring volumes ofliquids.2. Refer
3、enced Documents2.1 ASTM Standards:2E438 Specification for Glasses in Laboratory ApparatusE542 Practice for Calibration of Laboratory VolumetricApparatusE920 Specification for Commercially Packaged LaboratoryApparatusE921 Specification for Export Packaged Laboratory Appa-ratusE1133 Practice for Perfo
4、rmance Testing of Packaged Labo-ratory Apparatus for United States Government Procure-ments3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 accuracythe expected distribution of mean volumesaround the stated volume.3.1.2 coeffcient of variationthe expected distribution ofindivid
5、ual volumes around the mean volume.3.1.3 disposable pipetsin accordance with this specifica-tion and the expected product performance expressed in thisspecification, those serological pipets which are to be used onetime only. Any institution or individual who reuses a dispos-able pipet must bear ful
6、l responsibility for its safety andeffectiveness.4. Materials and Manufacture4.1 The pipets shall be fabricated from borosilicate glass,Type I, Class A or B; or soda-lime glass, Type II, as defined inSpecification E438.5. Design5.1 ShapePipets shall be straight and of one-piece con-struction. Any cr
7、oss section of a pipet taken in a planeperpendicular to the longitudinal axis shall be circular.5.2 Delivery TipsDelivery tips shall be made with agradual taper of 10 to 25 mm for capacities up to 2 cm3inclusive, and 15 to 30 mm for the 5-cm3and 10-cm3size(s).The tip end shall be reasonably perpendi
8、cular to the longitu-dinal axis of the pipet and shall be firepolished.5.3 Top EndThe 10-cm3and 25-cm3pipet shall have a topend tooled to a diameter of 7 to 9 mm and shall have an overalllength of 15 to 25 mm from the top. The top end shall besuitable for plugging with filtering material. All top en
9、ds shallbe reasonably perpendicular to the longitudinal axis of thepipet, and shall be firepolished.5.4 Dimensions and Outflow TimesThe limiting dimen-sions and outflow times shall be as shown in Table 1. Outflowtimes shall be determined on unplugged pipets, using distilledwater at 25 6 5C, and by m
10、eans of a stopwatch.6. Markings6.1 Graduation MarkingsGraduation lines shall be be-tween 0.2 and 0.5 mm in width, and in a plane perpendicular tothe longitudinal axis of the pipet and parallel to each other. Amain graduation line shall extend at least three-fifths of the wayaround the pipet. The val
11、ues of all main graduation lines shallbe in Arabic numerals directly above the line referenced.Intermediate graduation lines shall extend at least one-fifth ofthe way around the pipet, and least graduation lines shallextend at least one-seventh of the distance around the pipet.The 0 graduation line
12、shall be at least 90 mm below the top ofthe pipet on all sizes.6.2 Identification MarkingsEach pipet shall be markedwith the manufacturers or vendors name or trademark, itscapacity, the symbols “TD” (for “to deliver”) and “20C,” andeither a wide band or two narrow bands on the mouthpiece endto signi
13、fy that the last drop must be blown out to achieve fulldelivery.6.3 CapacityThe pipet capacity, expressed in cubic cen-timetres or millilitres, shall be stated on the package. Theexpected deviation from the stated capacity shall be based onunplugged pipets and expressed as accuracy and coefficient o
14、fvariation. Pipets shall be calibrated for delivery at 20C (seeSection 7).1This specification is under the jurisdiction of ASTM Committee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onApparatus.Current edition approved Nov. 1, 2009. Published December 2009. Ori
15、ginallyapproved in 1980. Last previous edition approved in 2004 as E714 94 (2004).DOI: 10.1520/E0714-94R09.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the stand
16、ards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Determination of Accuracy and Coefficient ofVariation7.1 Randomly select a minimum of 30 pipets and testgravimetrically, using distilled
17、 water.7.1.1 AccuracyThe accuracy shall be within the limits ofTable 2 and shall be determined as follows:A 5 X2 V1!/V13 100 (1)where:A = accuracy, %,X= mean of sample measurements, cm3, andV1= stated capacity of pipet, cm3.7.1.2 Coeffcient of VariationThe coefficient of variationshall be within the
18、 limits of Table 2 and shall be determined asfollows:CV 5100 SX(2)S 5 =(X 2 X!2!/n 2 1!# (3)where:CV = coefficient of variation, %,S = standard deviation,X = individual sample measurement, cm3,X= mean of sample measurements, cm3, andn = number of pipets measured.8. Workmanship, Finish, and Appearanc
19、e8.1 Pipets shall be free of defects that may impair theirserviceability, such as significant foreign matter or chips thataffect the bore.9. Packaging Requirements9.1 For packaging refer to either Specification E920 orE921.10. Keywords10.1 disposable; glass; pipets; serologicalASTM International tak
20、es no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own re
21、sponsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addres
22、sed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at th
23、e address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (ph
24、one), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE 1 Dimensions and Outflow TimesCapacity,cm3Least ValueMainNumberedGraduated 0to At Le
25、astOutside Diameter ofGraduated Portion,mmOutflow Time, sWallThickness,min, mmmin max0.1 0.01 0.01 0.09 3.5 to 4.0 0.5 3 1.00.2 0.01 0.02 0.18 3.5 to 4.5 0.5 3 1.00.2 0.01 0.05 0.18 3.5 to 4.5 0.5 3 1.00.5 0.01 0.1 0.40 4.25 to 4.75 0.5 3 0.81.0 0.01 0.1 0.90 4.25 to 4.75 0.5 5 0.81.0 0.1 0.1 0.9 4.
26、25 to 4.75 0.5 5 0.82.0 0.01 0.1 1.9 5.5 to 6.0 0.5 5 0.85.0 0.1 1.0 4.5 7.5 to 8.25 3.0 10 0.810.0 0.1 1.0 9.0 9.5 to 11.25 4.5 15 0.825.0 0.2 1.0 23.0 15.0 to 16.0 10.0 30 0.85TABLE 2 Accuracy and Coefficient of Variation of StatedCapacityCapacity, cm3Accuracy, %ACoefficient ofVariation, %A0.1 67 #2.50.2 66 #2.00.5 63 #1.51.0 63 #1.52.0 63 #1.55.0 63 #1.510.0 63 #1.525.0 63 #1.5AApplies only to the stated capacity.E714 94 (2009)2
