SIST ISO 12772:1998

INTERNATIONAL
STANDARD
12772
First edition
1997-05-o 1
Laboratory glassware - Disposable
microhaematocrit capillary tubes
Verrerie de labora toire - Tubes capillaires microh6matocrites & usage
unique
Reference number
IS0 12772: 1997(E)

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IS0 12772: 1997(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies
(IS0 member bodies). The work of preparing International Standards is normally carried out through IS0
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. IS0 collaborates 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 by at least 75 % of the member bodies
casting a vote.
This International Standard IS0 12772 has been prepared by Technical Committee lSO/TC 48, Laboratory
glassware and related apparatus, Subcommittee SC 1, Volumetric instruments.
Annexes A, B and C form an integral part of this International Standard. Annexes D and E are for information
only.
0 IS0 1997
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
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Printed in Switzerland

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INTERNATIONAL STANDARD @ IS0 IS0 12772: 1997(E)
Laboratory glassware - Disposable microhaematocrit
capillary tubes
1 Scope
This International Standard provides details for two types of disposable glass capillary tubes, suitable for the
microhaematocrit test and other analytical tests which include a separation of plasma and cells. The details
specified are in conformity with IS0 8417, to the greatest possible extent.
WARNING - Capillary tubes can break during the analytical test procedure, resulting in broken sharp glass,
blood spillage and aerosols. Appropriate precautions shall be taken to avoid dangerous infections.
2 Normative references
The following standards contain provisions which, through references in this text, constitute 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 standards indicated below. Members of IEC and IS0
maintain registers of currently valid International Standards.
IS0 719:1985, Glass - Hydrolytic resistance of glass grains at 98 OC - Method of test and classification.
IS0 8417:---l, Laboratory volumetric instruments - Principles of design and construction of disposable
volumetric articles.
3 Definition
For the purposes of this International Standard, the following definition applies.
3.1 disposable: Adjective used to describe microhaematocrit capillary tubes which are intended to be used
once only and then discarded.
NOTE - Such capillary tubes will only be expected to provide their specified performance during the original operation.
4 Classification
This International Standard describes two types of disposable glass capillary tubes as follows:
- Type I: coated with anti-coagulant
- Type II: uncoated
lithium heparin and sodium heparin are the preferred anti-coagulants for the
NOTE - Ammonium heparin,
21
microhaematocrit test. Salts of EDTA and fluorides (usually sodium or potassium) may be used when capillary tubes are
needed for special purposes.
‘) To be published.
2, EDTA is a n abbreviation for ethylenediaminotetraacetic acid

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@ IS0
IS0 12772:1997(E)
5
Construction
5.1 Material
When tested in accordance with the procedure and classification given in IS0 719, the glass used for the
capillary tubes shall at least comply with the requirements of class HGB 3.
The glass shall be free from visible defects and shall be free from internal stresses which would impair the
performance of the capillary tube.
5.2 Design
The tubes shall be straight and open at both ends without lip or constriction. The tubes may be slightly fire-
polished on one or both ends.
5.3 Dimensions
The dimensions of the tubes shall be as follows:
Length: (752 0,5) mm
Internal diameter: (I,15 + 0,081 mm
Wall thickness: (0,2+0,025) mm
The bore of the tubes shall be uniform and shall not vary by more than 4 % of the total over a distance of 75
mm.
critical for the analytical result, smaller bore variations than 4 % may be marked on the
NOTE - As the bore variation is
packaging of the capillary tubes.
5.4 Ring mark
The tubes may be provided with a ring mark to ease filling. Such a ring mark shall be at a distance of 60 mm
max. from one end of the tube. The line thickness shall be between 0,5 mm and 1 mm.
In the case of colour-coded tubes (see 6.2), the colour of the ring mark should preferably be that of the colour
code, or may be black.
force
5.5 Resistance to centrifugal
specified in annex A, not more than 0,5 % shall break.
When the tubes are tested as
5.6 Capillarity
The tube shall be capable of drawing plasma, serum or human whole blood to a level within 20 mm from the
far end of the tube when tested as specified in annex B.
NOTE - In view of the possible infection risks, human blood should not be used.
5.7 Anti-coagulant (Type I only)
The inner surface of Type I tubes shall be evenly coated with an anti-coagulant (see clause 4). In the case of
heparin, the coating shall show an activity of 2,13 IU to 7,45 IU (International Units) per capillary when tested
as described in annex E. An airtight container should be used in order to prevent deterioration of the anti-
coagulant caused by air moisture.

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0 IS0 IS0 12772: 1997(E)
5.8 Efficacy of heparin coating (Type I only)
.
Coagu latr on of the sheep plasm a shall not be ev ident when viewed under normal room lighting . This can be
tested as described in ann ex D.
6
Markings
6.1 Labelling
The outer shipping carton shall be clearly marked with the following information:
a) manufacturer’s or vendor’s name and/or mark;
b) product description (e.g. disposable microhaematocrit capillary tubes) and the glass material (e.g.
borosilicate glass 3.3 or soda-lime glass);
c) number of tubes in the package;
d) batch number or date of manufacture;
e) the number of this International Standard, i.e. IS0 12772;
and, if applicable (Type I only):
f) type of anti-coagulant (e.g. lithium heparin);
...