EN ISO 5814:2012
(Main)Water quality - Determination of dissolved oxygen - Electrochemical probe method (ISO 5814:2012)
Water quality - Determination of dissolved oxygen - Electrochemical probe method (ISO 5814:2012)
ISO 5814:2012 specifies an electrochemical method for the determination of dissolved oxygen in water by means of an electrochemical cell which is isolated from the sample by a gas permeable membrane.
Measurement can be made either as a concentration of oxygen in milligrams per litre, percentage saturation (% dissolved oxygen) or both. The method measures oxygen in water corresponding to 1 % to 100 % saturation. However, most instruments permit measurement of values higher than 100 %, i.e. supersaturation.
The method measures oxygen in water with a saturation higher than 100 %, when special arrangements to prevent the outgassing of oxygen during the handling and measurement of the sample are made.
The method is suitable for measurements made in the field and for continuous monitoring of dissolved oxygen, as well as measurements made in the laboratory. It is the preferred method for highly coloured and turbid waters, and also for analysis of waters not suitable for the Winkler titration method because of iron- and iodine-fixing substances, which can interfere in the iodometric method specified in ISO 5813.
The method is suitable for drinking waters, natural waters, waste waters, and saline waters. If used for saline waters, such as sea or estuarine waters, a correction for salinity is essential.
Wasserbeschaffenheit - Bestimmung des gelösten Sauerstoffs - Elektrochemisches Verfahren (ISO 5814:2012)
Diese Internationale Norm legt ein elektrochemisches Verfahren zur Bestimmung von gelöstem Sauerstoff in
Wasser mittels einer elektrochemischen Zelle, die von der Probe durch eine gasdurchlässige Membran
getrennt ist, fest.
Das Messergebnis kann als Massenkonzentration an gelöstem Sauerstoff in Milligramm je Liter (mg/l)
und/oder als relative Sättigung in Prozent (%) angegeben werden. Das Verfahren ist anwendbar zur
Bestimmung der relativen Sättigung im Bereich von 1 % bis 100 %. Mit den meisten Geräten lässt sich auch
eine relative Sättigung über 100 % (Übersättigung) bestimmen.
ANMERKUNG Eine Übersättigung ist möglich, wenn der Sauerstoffpartialdruck in der Wasserprobe höher ist als in der
atmosphärischen Luft. Besonders im Fall von starkem Algenwachstum ist eine Übersättigung von bis zu 200 % und mehr
möglich.
Bei einer relativen Sättigung von über 100 % ist die Bestimmung von Sauerstoff dann möglich, wenn
besondere Vorkehrungen getroffen werden, um eine Ausgasung von Sauerstoff während der Handhabung
und der Messung der Probe zu vermeiden.
Das Verfahren ist für die Messung des gelösten Sauerstoffs vor Ort, für kontinuierliche Messungen und für
Labormessungen geeignet. Es ist das bevorzugte Verfahren für stark gefärbte und trübstoffhaltige Wässern,
sowie für Wässer, die eisen- und iodbindende Stoffe enthalten und die sich somit nicht für die titrimetrische
Bestimmung nach Winkler eignen (Iodometrisches Verfahren nach ISO 5813, [1]).
Das Verfahren ist für Trink-, Grund-, Oberflächen- und Abwässer sowie für salzhaltige Wässer geeignet. Falls
die Messung in salzhaltigen Wässern, wie Meer- und Brackwasser, durchgeführt wird, ist eine Korrektur des
Messsignals in Abhängigkeit von der Salinität erforderlich.
Qualité de l'eau - Dosage de l'oxygène dissous - Méthode électrochimique à la sonde (ISO 5814:2012)
L'ISO 5814:2012 spécifie une méthode électrochimique de dosage de l'oxygène dissous dans l'eau à l'aide d'une cellule électrochimique qui est isolée de l'échantillon par une membrane perméable aux gaz.
Le mesurage peut être fait soit en tant que concentration en oxygène, en milligrammes par litre, soit en tant que pourcentage de saturation (% d'oxygène dissous) ou les deux. La méthode mesure l'oxygène dans l'eau correspondant à un taux de saturation de 1 % à 100 %. Cependant, la plupart des appareils permettent des mesurages de valeurs supérieures à 100 %, c'est-à-dire une sursaturation.
La méthode mesure l'oxygène dans l'eau avec une saturation supérieure à 100 %, lorsque des mesures spécifiques sont mises en ?uvre pour empêcher le dégazage de l'oxygène pendant la manipulation et le mesurage de l'échantillon.
La méthode est utilisable pour les mesurages effectués sur le terrain et pour le contrôle permanent de l'oxygène dissous, ainsi que pour les mesurages en laboratoire. C'est la méthode à préférer pour les eaux fortement colorées et troubles, ainsi que pour l'analyse des eaux inadaptées à la méthode de titrage de Winkler en raison des substances fixant le fer et l'iode susceptibles d'interférer avec la méthode iodométrique spécifiée dans l'ISO 5813.
La méthode est utilisable pour les eaux potables, les eaux naturelles, les eaux résiduaires et les eaux salines. Si elle est utilisée pour des eaux salines telles que les eaux de mers ou les eaux d'estuaires, une correction due à la salinité est essentielle.
Kakovost vode - Določevanje raztopljenega kisika - Elektrokemijska metoda (ISO 5814:2012)
Ta mednarodni standard opisuje elektrokemijsko metodo za določevanje raztopljenega kisika v vodi z elektrokemijsko celico, ki je od vzorca izolirana z membrano, ki prepušča pline. Meritev se lahko opravi kot koncentracija kisika v miligramih na liter, odstotek nasičenosti (% raztopljenega kisika) ali oboje. Metoda meri kisik v vodi, ki ustreza od 1 % do 100 % nasičenosti. Vendar večina instrumentov omogoča meritve vrednosti, višje od 100 %, tj. prenasičenost. Metoda meri kisik v vodi pri nasičenosti, višji od 100 %, kadar so uvedeni posebni ukrepi za preprečevanje samorazplinjenja kisika med ravnanjem z vzorcem in meritvami v zvezi z njim. Metoda je primerna za meritve na terenu in za neprestano spremljanje raztopljenega kisika ter tudi za meritve v laboratoriju. To je prednostna metoda za zelo obarvane in motne vode ter tudi za analizo vod, ki zaradi vsebnosti snovi, ki fiksirajo železo in jod ter lahko povzročajo motnje pri jodometrijski metodi iz standarda ISO 5813[1], niso primerne za titracijo po Winklerju. Metoda je primerna za pitne vode, naravne vode, odpadne vode in slane vode. Če se uporablja za slane vode, npr. za morske vode ali somornice, je potrebna korekcija za slanost.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2013
1DGRPHãþD
SIST EN 25814:1996
.DNRYRVWYRGH'RORþHYDQMHUD]WRSOMHQHJDNLVLND(OHNWURNHPLMVNDPHWRGD ,62
Water quality - Determination of dissolved oxygen - Electrochemical probe method (ISO
5814:2012)
Wasserbeschaffenheit - Bestimmung des gelösten Sauerstoffs - Elektrochemisches
Verfahren (ISO 5814:2012)
Qualité de l'eau - Dosage de l'oxygène dissous - Méthode électrochimique à la sonde
(ISO 5814:2012)
Ta slovenski standard je istoveten z: EN ISO 5814:2012
ICS:
13.060.50 3UHLVNDYDYRGHQDNHPLþQH Examination of water for
VQRYL chemical substances
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN ISO 5814
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2012
ICS 13.060.50 Supersedes EN 25814:1992
English Version
Water quality - Determination of dissolved oxygen -
Electrochemical probe method (ISO 5814:2012)
Qualité de l'eau - Dosage de l'oxygène dissous - Méthode Wasserbeschaffenheit - Bestimmung des gelösten
électrochimique à la sonde (ISO 5814:2012) Sauerstoffs - Elektrochemisches Verfahren (ISO
5814:2012)
This European Standard was approved by CEN on 4 August 2012.
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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 5814:2012: E
worldwide for CEN national Members.
Contents Page
Foreword .3
Foreword
This document (EN ISO 5814:2012) has been prepared by Technical Committee ISO/TC 147 “Water quality”
in collaboration with Technical Committee CEN/TC 230 “Water analysis” 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 April 2013, and conflicting national standards shall be withdrawn at the
latest by April 2013.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 25814:1992.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 5814:2012 has been approved by CEN as a EN ISO 5814:2012 without any modification.
INTERNATIONAL ISO
STANDARD 5814
Third edition
2012-10-15
Water quality — Determination of dissolved
oxygen — Electrochemical probe method
Qualité de l’eau — Dosage de l’oxygène dissous — Méthode
électrochimique à la sonde
Reference number
ISO 5814:2012(E)
©
ISO 2012
ISO 5814:2012(E)
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 either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved
ISO 5814:2012(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Principle . 1
4 Interferences . 2
5 Reagents . 2
6 Apparatus . 2
7 Sampling and analysis procedure . 3
7.1 Sampling . 3
7.2 Measuring technique and precautions to be taken . 3
7.3 Calibration . 4
7.4 Determination . 4
8 Calculation and expression of results . 5
8.1 Dissolved oxygen concentration . 5
8.2 Dissolved oxygen expressed as percentage saturation . 5
9 Test report . 5
Annex A (informative) Physicochemical data for oxygen in water . 6
Annex B (informative) Performance data .12
Bibliography .14
ISO 5814:2012(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. 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.
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.
ISO 5814 was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 2, Physical,
chemical and biochemical methods.
This third edition cancels and replaces the second edition (ISO 5814:1990), which has been technically revised.
The main changes compared to the second edition are:
a) a calibration procedure using water-saturated air is specified;
b) the calibration procedure using air-saturated water is omitted.
iv © ISO 2012 – All rights reserved
INTERNATIONAL STANDARD ISO 5814:2012(E)
Water quality — Determination of dissolved oxygen —
Electrochemical probe method
WARNING — Persons using this International Standard should be familiar with normal laboratory
practice. This standard does not purport to address all of the safety problems, if any, associated with
its use. It is the responsibility of the user to establish appropriate safety and health practices and to
ensure compliance with any national regulatory conditions.
IMPORTANT — It is absolutely essential that tests conducted according to this International Standard
be carried out by suitably trained staff.
1 Scope
This International Standard specifies an electrochemical method for the determination of dissolved oxygen in
water by means of an electrochemical cell which is isolated from the sample by a gas permeable membrane.
Measurement can be made either as a concentration of oxygen in milligrams per litre, percentage saturation (%
dissolved oxygen) or both. The method measures oxygen in water corresponding to 1 % to 100 % saturation.
However, most instruments permit measurement of values higher than 100 %, i.e. supersaturation.
NOTE Supersaturation is possible when the partial pressure of oxygen is higher than in air. Especially when strong
algal growth is present, supersaturation of up to 200 % and above can occur.
The method measures oxygen in water with a saturation higher than 100 %, when special arrangements to
prevent the outgassing of oxygen during the handling and measurement of the sample are made.
The method is suitable for measurements made in the field and for continuous monitoring of dissolved oxygen,
as well as measurements made in the laboratory. It is the preferred method for highly coloured and turbid
waters, and also for analysis of waters not suitable for the Winkler titration method because of iron- and iodine-
[1]
fixing substances, which can interfere in the iodometric method specified in ISO 5813 .
The method is suitable for drinking waters, natural waters, waste waters, and saline waters. If used for saline
waters, such as sea or estuarine waters, a correction for salinity is essential.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable
for its application. For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
ISO 3696, Water for analytical laboratory use — Specification and test methods
3 Principle
Immersion of a probe, consisting of a cell enclosed by a selective membrane and containing the electrolyte and
at least two metallic electrodes, in the water to be analysed.
NOTE The membrane is effectively impermeable to water and ionic dissolved matter, but is permeable to oxygen and
a certain number of other gases.
One of the electrodes is made of a noble metal like gold or platinum. Oxygen is reduced at its surface by
an electrochemical process. In order to make this process possible, a suitable electrochemical potential is
established at this electrode. For polarographic probes, this is achieved by applying an external voltage related
to a second electrode. Galvanic probes are able to build up the potential by themselves.
ISO 5814:2012(E)
The current resulting from the reduction of oxygen is directly proportional to the rate of transport of oxygen
through the membrane and the layer of electrolyte, and hence to the partial pressure of the oxygen in the
sample at a given temperature.
Temperature has two different influences. The first relates to the variation of gas permeability of the membrane
with temperature. So the primary signal of the probe has to be compensated with a built-in temperature sensor.
Meters manufactured recently are able to do this automatically. The second is the temperature effect on the
electrode reactions.
To calculate the percentag
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.