SIST EN ISO 8655-2:2022

SLOVENSKI STANDARD
01-julij-2022
Nadomešča:
SIST EN ISO 8655-2:2002
SIST EN ISO 8655-2:2002/AC:2009
Volumetrične naprave, delujoče na bat - 2. del: Pipete (ISO 8655-2:2022)
Piston-operated volumetric apparatus - Part 2: Pipettes (ISO 8655-2:2022)
Volumenmessgeräte mit Hubkolben - Teil 2: Pipetten (ISO 8655-2:2022)
Appareils volumétriques à piston - Partie 2: Pipettes (ISO 8655-2:2022)
Ta slovenski standard je istoveten z: EN ISO 8655-2:2022
ICS:
17.060 Merjenje prostornine, mase, Measurement of volume,
gostote, viskoznosti mass, density, viscosity
71.040.20 Laboratorijska posoda in Laboratory ware and related
aparati apparatus
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 8655-2
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2022
EUROPÄISCHE NORM
ICS 17.060 Supersedes EN ISO 8655-2:2002, EN ISO 8655-
2:2002/AC:2009
English Version
Piston-operated volumetric apparatus - Part 2: Pipettes
(ISO 8655-2:2022)
Appareils volumétriques à piston - Partie 2: Pipettes Volumenmessgeräte mit Hubkolben - Teil 2: Pipetten
(ISO 8655-2:2022) (ISO 8655-2:2022)
This European Standard was approved by CEN on 13 February 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC 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
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 8655-2:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 8655-2:2022) has been prepared by Technical Committee ISO/TC 48
"Laboratory equipment" 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 the latest by November 2022, and conflicting national standards
shall be withdrawn at the latest by November 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 8655-2:2002.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 8655-2:2022 has been approved by CEN as EN ISO 8655-2:2022 without any
modification.
INTERNATIONAL ISO
STANDARD 8655-2
Second edition
2022-04
Piston-operated volumetric
apparatus —
Part 2:
Pipettes
Appareils volumétriques à piston —
Partie 2: Pipettes
Reference number
ISO 8655-2:2022(E)
ISO 8655-2:2022(E)
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 8655-2:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle of operation . 2
5 Adjustment .2
5.1 Basis of adjustment . 2
5.2 Initial adjustment . 2
5.3 Subsequent adjustment . 2
5.4 Adjustment for other liquid properties . 2
6 Design . 3
6.1 Types of pipette . 3
6.2 Transfer of hand warmth . 3
7 Pipette tips . 4
7.1 General . 4
7.2 Air-displacement pipette tips . 4
7.3 Positive-displacement pipette tips . 4
8 Type, designation . 5
9 Metrological performance requirements . 5
9.1 General . 5
9.2 Fixed-volume pipettes of types A and D1 . 5
9.3 Fixed-volume pipettes of type D2 . 5
9.4 Variable-volume pipettes of types A, D1 and D2 . 6
9.5 Multi-channel pipettes . 6
9.6 Calculation of maximum permissible errors for volumes not listed in Tables 1, 2
and 3 . 6
9.7 Pipette tips . 9
10 User information . 9
10.1 Pipettes . 9
10.2 Pipette tips and accessories. 10
11 Marking . .10
11.1 Pipettes . 10
11.2 Pipette tips . 10
Annex A (informative) Possible sources of error for air displacement pipettes .11
Annex B (informative) Electronic motorised air displacement pipettes and method
for testing in multi-dispensing mode .13
Bibliography .15
iii
ISO 8655-2:2022(E)
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 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, governmental 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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 48, Laboratory equipment, in collaboration
with the European Committee for Standardization (CEN) Technical Committee CEN/TC 332, Laboratory
equipment, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna
Agreement).
This second edition cancels and replaces the first edition (ISO 8655-2:2002), which has been technically
revised. It also incorporates the Technical Corrigendum ISO 8655-2:2002/Cor.1:2008.
The main changes are as follows:
— ISO 8655-7 and ISO 8655-8 have been added as normative references;
— metrological performance requirements for pipette tips have been further specified;
— Tables 1 and 2 have been revised;
— a new Table 3 has been introduced;
— a new informative Annex B for motorised pipettes has been introduced;
— former Annex A has been added as new Clause 10.
A list of all parts in the ISO 8655 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
ISO 8655-2:2022(E)
Introduction
The ISO 8655 series addresses the needs of:
— manufacturers, as a basis for quality control including, where appropriate, the issuance of
manufacturer’s declarations;
— calibration laboratories, test houses, users of the equipment and other bodies as a basis for
independent calibration, testing, verification and routine tests.
The tests specified in the ISO 8655 series are intended to be carried out by trained personnel.
v
INTERNATIONAL STANDARD ISO 8655-2:2022(E)
Piston-operated volumetric apparatus —
Part 2:
Pipettes
1 Scope
This document specifies
— metrological requirements,
— maximum permissible errors,
— requirements for marking and
— information to be provided for users,
for air-displacement (type A) and positive displacement (type D) single-channel and multi-channel
pipettes, complete with their selected tip(s) and any other essential, consumable parts, designed to
deliver the selected volume (Ex).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods
ISO 8655-1, Piston-operated volumetric apparatus — Part 1: Terminology, general requirements and user
recommendations
ISO 8655-6:2022, Piston-operated volumetric apparatus — Part 6: Gravimetric reference measurement
procedure for the determination of volume
ISO 8655-7:2022, Piston operated volumetric apparatus — Part 7: Alternative measurement procedures
for the determination of volume
ISO 8655-8:2022, Piston-operated volumetric apparatus — Part 8: Photometric reference measurement
procedure for the determination of volume
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8655-1 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
ISO 8655-2:2022(E)
4 Principle of operation
Pipettes are used to accurately handle preselected volumes. A tip is attached to the pipette. Pipettes
are typically operated using forward pipetting. Using forward pipetting, with the piston positioned at
the lower aspiration limit, the tip is dipped into the liquid to be dispensed. When moved to the upper
aspiration limit, the piston aspirates the liquid. The liquid volume to be dispensed is then expelled by
depressing or sliding the piston between the volume-defining limits. Some air-displacement pipettes
(see 6.1, Type A) have an extra air volume that can be used to expel the last drop of liquid.
See also Figure 1.
Manufacturers' instruction manuals should contain detailed and specific information about the proper
operation of pipettes.
5 Adjustment
5.1 Basis of adjustment
A pipette shall be adjusted for the delivery (Ex) of its nominal volume (or selected volume, in the case of
a variable-volume model).
For countries that have adopted the standard reference temperature of 20 °C, the adjustment shall be
for the temperature of 20 °C, a relative air humidity of 50 % and a barometric pressure of 101,3 kPa,
when handling grade 3 water as specified in ISO 3696:1987.
For those countries that have adopted a standard reference temperature of 27 °C, the adjustment shall
be for the temperature 27 °C, a relative air humidity of 50 % and a barometric pressure of 101,3 kPa,
when handling grade 3 water as specified in ISO 3696:1987.
5.2 Initial adjustment
A pipette shall be provided with an initial adjustment.
5.3 Subsequent adjustment
Some pipettes have provision for adjustment when, for example, it is found in a routine check that
the volume delivered is not within specification. Such adjustment shall be made in accordance with
the manufacturer's instructions and by reference to a measurement procedure in accordance with
ISO 8655-6, ISO 8655-7 or ISO 8655-8.
Any pipette so adjusted shall have clear, visible evidence that the initial adjustment has been modified.
This information shall also be recorded.
5.4 Adjustment for other liquid properties
Some pipettes are designed to have their factory pre-set adjustment altered by the user so that they will
dispense their specified volume when used with liquids with physical properties differing from those
of water (see Annex A for details). In such cases, the design shall prevent unintentional readjustment.
Such adjustment shall be made in accordance with the manufacturer's instructions or by reference to
the selected test procedure from ISO 8655-7 and the modifications made.
If the pipette is readjusted, it shall be clearly and unequivocally indicated on the outside of the pipette
that readjustment has been affected. The outside of the pipette shall be marked with the name of the
liquid and the adjusted volume range. This information shall be documented appropriately.
ISO 8655-2:2022(E)
6 Design
6.1 Types of pipette
A pipette may be designed as follows:
— fixed volume, designed by the manufacturer to dispense only its nominal volume, e.g. 100 μl;
— variable volume, designed by the manufacturer to dispense volumes selectable by the user within
its specified usable volume range, e.g. between 10 μl and 100 μl.
The piston may:
— either have a body of air contained between the piston and the surface of the liquid (air displacement
– Type A); or
— be in direct contact with the surface of the liquid (positive or direct displacement – Type D).
In the case of the Type D pipette, either the plunger or the capillary, or both may be reusable (Type D1)
or disposable (Type D2). See Figure 1 for details.
Type D Type A
Positive (direct) displacement Air displacement
a)  Single-channel pipettes b)  Multi-channel pipette
Figure 1 — Pipettes
6.2 Transfer of hand warmth
The construction of pipettes and the materials used for their manufacture shall be chosen in such a way
that any heat transmitted from the user's hand to the apparatus during periods of use is minimized.
NOTE Transfer of hand warmth will appear as a systematic drift of results (the delivered volume decreases
over time) during a series of deliveries.
...