ASTM E788-97(2019)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E788 −97 (Reapproved 2019)
Standard Specification for
Pipet, Blood Diluting
This standard is issued under the fixed designation E788; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 4. Materials
1.1 Thisspecificationcoversrequirementsforglassreusable 4.1 The pipets shall be made of common spirit bore white
blooddilutingpipetsthatareusedforperformingredandwhite back tubing or clear glass with a white stripe applied to the
cell corpuscle determinations. outer surface of the tubing.
1.2 The values stated in SI units are to be regarded as 4.2 The beads shall be made of glass or ceramic composi-
standard. No other units of measurement are included in this tion and shall be of red, clear, or white coloring.
standard.
5. Dimensions and Permissible Variations
1.3 This international standard was developed in accor-
5.1 Design—The red and white cell blood dilution pipets
dance with internationally recognized principles on standard-
shall consist of a small uniform bore glass tube which shall
ization established in the Decision on Principles for the
have a bulb of proper size near the proximal end (see Fig. 1).
Development of International Standards, Guides and Recom-
As an alternative, the pipets may be constructed of three pieces
mendations issued by the World Trade Organization Technical
of glass that are fused together to form a one-piece pipet (see
Barriers to Trade (TBT) Committee.
Fig. 2). The bulb shall contain a nonspherical glass or ceramic
bead sufficiently large enough to prevent its being impacted in
2. Referenced Documents
the constriction portion of the bulb. The cross section of the
2.1 ASTM Standards:
pipet at any point shall be circular. The distal end of the white
E694 Specification for Laboratory Glass Volumetric Appa-
cell pipet shall be pulled to a point and then ground and
ratus
polished to a tapered tip. The distal end of the red cell pipet
E920 Specification for Commercially Packaged Laboratory
shall be ground and polished to a tapered tip. The inside
Apparatus
diameter (ID) of the pipet bore at the tip end of the white cell
E921 Specification for Export Packaged Laboratory Appa-
pipet shall be 0.2 to 0.5 mm. The external diameter of the
ratus
ground and polished tip shall not exceed 2.0 mm. The overall
E1133 Practice for Performance Testing of Packaged Labo-
lengthofbothpipetsshallbe104to121mm.Theproximalend
ratory Apparatus for United States Government Procure-
may be of funnel design, with an exterior taper, or ground and
ments
polishedwithataperofsufficientangletopermitapplicationof
E1157 Specification for Sampling and Testing of Reusable
a rubber suction tube or other suction device (see Fig. 2).
Laboratory Glassware
5.2 Capacity—The capacity of the red cell pipet bulb shall
3. Classification be 0.8 to 1.2 cm and the capacity of the white cell bulb shall be
0.2 to 0.4 cm . The capacity of the red cell pipet stem (bulb to
3.1 This specification covers two different pipet designs and
distal end) shall be 0.008 to 0.012 cm and the capacity of the
permissible alternatives.
white cell pipet stem shall be 0.02 to 0.04 cm .
3.1.1 Red and white cell blood diluting pipets (see Fig. 1).
3.1.2 Permissible alternative designs (see Fig. 2). 5.3 Capacity Markings:
5.3.1 Pipet Bulb Markings—The red and white cell pipet
bulb capacity shall be confined to and indicated by calibration
This specification is under the jurisdiction of ASTM Committee E41 on
lines on the pipet. These lines shall be located on both sides of
Laboratory Apparatus and is the direct responsibility of Subcommittee E41.01 on
the bulb and shall be within 2 mm to 6 mm above the bulb
Laboratory Ware and Supplies.
(proximalend)andwithin3mmto6mmbelowthebulb(distal
Current edition approved July 1, 2019. Published August 2019. Originally
end). The exact manner for measuring these line placements is
approvedin1981.Lastpreviouseditionapprovedin2013asE788 – 97(2013).DOI:
10.1520/E0788-97R19.
specified in Fig. 1.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
5.3.2 Pipet Stem Markings—The graduation lines on the
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
stem of the red and white cell pipets shall be equally divided
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. into two or ten divisions. If there are two divisions, the two
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E788 − 97 (2019)
FIG. 1 Pipet Dimensions
calibration lines on the stem will be numbered 0.5 and 1. If 5.6.2 Construction shall be such that the mechanical
there are ten divisions, the ten calibration lines will be strength is provided to withstand the rigors of normal use. The
numbered 0.5 on the fifth line and 1 on the tenth line pipets shall be free of strain when tested in accordance with
respectively. The top line (above bulb at the proximal end)
6.4.
shall be numbered 101 on the red cell pipet and 11 on the white
5.7 Identification—Each pipet shall have the name or regis-
cell pi
...