ASTM D5462-08

Standard Test Method for On-Line Measurement of Low-Level Dissolved Oxygen in Water

SIGNIFICANCE AND USE
DO may be either a corrosive or passivating agent in boiler/steam cycles and is therefore controlled to specific concentrations that are low relative to environmental and wastewater treatment samples. Out-of-specification DO concentrations may cause corrosion in boiler systems, which leads to corrosion fatigue and corrosion products—all detrimental to the life and efficient operation of a steam generator. The efficiency of DO removal from boiler feedwater by mechanical or chemical means, or both, may be monitored by continuously measuring the DO concentration before and after the removal process with on-line instrumentation. DO measurement is also a check for air leakage into the boiler water cycle.
Guidelines for feedwater to high-pressure boilers with all volatile treatment generally require a feedwater DO concentration below 5 μg/L (3).
Boiler feedwater with oxygenated treatment is maintained in a range of 50 to 300 μg/L DO (4).
In microelectronics production, DO can be detrimental in some manufacturing processes, for example, causing undesirable oxidation on silicon wafers.
SCOPE
1.1 This test method covers the on-line determination of dissolved oxygen (DO) in water samples primarily in ranges from 0 to 500 μg/L (ppb), although higher ranges may be used for calibration. On-line instrumentation is used for continuous measurements of DO in samples that are brought through sample lines and conditioned from high-temperature and high-pressure sources when necessary.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazards statements, see 6.5.

General Information

• Status: Historical
• Publication Date: 30-Apr-2008
• ICS: 13.060.50 - Examination of water for chemical substances
• Technical Committee: D19 - Water
• Drafting Committee: D19.03 - Sampling Water and Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, On-Line Water Analysis, and Surveillance of Water

Relations

• Replaces: ASTM D5462-02 - Standard Test Method for On-Line Measurement of Low-Level Dissolved Oxygen in Water
• Effective Date: 01-May-2008
• Referred By: ASTM D5127-13(2018) - Standard Guide for Ultra-Pure Water Used in the Electronics and Semiconductor Industries
• Effective Date: 01-May-2008

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D5462 − 08
StandardTest Method for
On-Line Measurement of Low-Level Dissolved Oxygen in
1
Water
This standard is issued under the fixed designation D5462; 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 3.2 Definitions of Terms Specific to This Standard:
3.2.1 diffusion-type probes—galvanic or polarographic sen-
1.1 This test method covers the on-line determination of
sors that depend on the continuous influx of oxygen through
dissolved oxygen (DO) in water samples primarily in ranges
the membrane to develop the electrical signal.
from 0 to 500 µg/L(ppb), although higher ranges may be used
3.2.2 equilibrium-type probes—modified polarographic
for calibration. On-line instrumentation is used for continuous
sensing probes that have a negligible influx of oxygen through
measurements of DO in samples that are brought through
the membrane except during changes of sample DO concen-
sample lines and conditioned from high-temperature and high-
tration. Oxygen consumption and regeneration balance each
pressure sources when necessary.
otherwithintheprobesunderstableconditions,andthenetflux
1.2 The values stated in SI units are to be regarded as
through the membrane is insignificant.
standard. No other units of measurement are included in this
3.2.3 galvanic systems—sensing probes and measuring in-
standard.
struments that develop an electrical current from two elec-
1.3 This standard does not purport to address all of the
trodes inside the probe from which the final measurement is
safety concerns, if any, associated with its use. It is the
derived.
responsibility of the user of this standard to establish appro-
3.2.4 partial pressure (of oxygen)—the volume fraction of
priate safety and health practices and determine the applica-
oxygen multiplied by the total pressure.The partial pressure of
bilityofregulatorylimitationspriortouse.Forspecifichazards
oxygenistheactualparameterdetectedbyDOprobes,whether
statements, see 6.5.
in air or dissolved in water.
2. Referenced Documents
3.2.5 polarographic systems—sensing probes and measur-
2
2.1 ASTM Standards:
ing instruments that include circuitry to control the operating
D1066 Practice for Sampling Steam
voltage of the system, usually using a third (reference) elec-
D1129 Terminology Relating to Water
trode in the probe.
D1193 Specification for Reagent Water
4. Summary of Test Method
D2777 Practice for Determination of Precision and Bias of
Applicable Test Methods of Committee D19 on Water
4.1 Dissolved oxygen is measured by means of an electro-
D3370 Practices for Sampling Water from Closed Conduits
chemical cell separated from the sample by a gas-permeable
D3864 Guide for Continual On-Line Monitoring Systems
membrane. Behind the membrane and inside the probe, elec-
for Water Analysis
trodes immersed in an electrolyte develop an electrical current
proportional to the oxygen partial pressure of the sample.
3. Terminology
4.2 The partial pressure signal is temperature compensated
3.1 Definitions—For definitions of terms used in this test
automatically to account for variations with temperature of the
method, refer to Terminology D1129.
following: oxygen solubility in water; electrochemical cell
output; and, when necessary, diffusion rate of oxygen through
1
This test method is under the jurisdiction of ASTM Committee D19 on Water
the membrane. This yields a direct readout in concentration of
and is the direct responsibility of Subcommittee D19.03 on Sampling Water and
µg/L (ppb) or mg/L (ppm).
Water-Formed Deposits,Analysis of Water for Power Generation and Process Use,
On-Line Water Analysis, and Surveillance of Water.
4.3 Diffusion-type probes rely on a continuous diffusion of
Current edition approved May 1, 2008. Published May 2008. Originally
oxygen through the membrane. Immediately inside the
approved in 1993. Last previous edition approved in 2002 as D5462 – 02. DOI:
10.1520/D5462-08.
membrane, oxygen is reduced at the noble metal cathode,
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
usually platinum or gold. An electrical current is developed
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
that is directly proportional to the arrival rate of oxygen
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. molecules at the cathode, which is in turn dependent on the
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D5462 − 08
diffusion
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:D5462–02 Designation:D5462–08
Standard Test Method for
On-Line Measurement of Low-Level Dissolved Oxygen in
1
Water
This standard is issued under the fixed designation D 5462; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the on-line determination of dissolved oxygen (DO) in water samples primarily in ranges from 0
to 500 µg/L (ppb), although higher ranges may be used for calibration. On-line instrumentation is used for continuous
measurements of DO in samples that are brought through sample lines and conditioned from high-temperature and high-pressure
sources when necessary.
1.2
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use. For specific hazards statements, see 6.5.
2. Referenced Documents
2
2.1 ASTM Standards:
D 1066 Practice for Sampling Steam
2
D 1129Terminology Relating to Water
2
D1192Specification for Equipment for Sampling Water and Steam in Closed Conduits Terminology Relating to Water
D 1193 Specification for Reagent Water
D 2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D-19D19 on Water
D 3370 Practices for Sampling Water from Closed Conduits
D 3864Practice Guide for Continual On-Line Monitoring Systems for Water Analysis
3. Terminology
3.1 Definitions—For definitions of terms used in this test method, refer to Terminology D 1129.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 diffusion-type probes—galvanic or polarographic sensors that depend on the continuous influx of oxygen through the
membrane to develop the measurementelectrical signal.
3.2.2 equilibrium-type probes—modified polarographic sensing probes that have a negligible influx of oxygen through the
membrane except during changes of sample DO concentration. Oxygen consumption and regeneration balance each other within
the probes under stable conditions, and the net flux through the membrane is insignificant.
3.2.3 galvanic systems—sensingprobesandmeasuringinstrumentsthatdevelopanelectricalcurrentfromtwoelectrodesinside
the probe from which the final measurement is derived.
3.2.4 partial pressure (of oxygen)—the volume fraction of oxygen multiplied by the total pressure. The partial pressure of
oxygen is the actual parameter detected by DO probes, whether in air or dissolved in water.
3.2.5 polarographic systems—sensing probes and measuring instruments that include circuitry to control the operating voltage
of the system, usually using a third (reference) electrode in the probe.
1
This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.03 on Sampling of Water and
Water-Formed Deposits, Surveillance of Water, and Flow Measurement of Water.
Current edition approved June 10, 2002. Published August 2002. Originally published as D5462–93. Last previous edition D5462–93(01).
1
This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.03 on Sampling Water and
Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, On-Line Water Analysis, and Surveillance of Water.
Current edition approved May 1, 2008. Published May 2008. Originally approved in 1993. Last previous edition approved in 2002 as D 5462 – 02.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
, Vol 11.01.volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
D5462–08
4. Summary of Test Method
4.1 Dissolved oxygen is measured by means of an electrochemical cell separated from the sample by a gas-permeable
membrane. Behind the membrane and inside the probe, electrodes immersed in an
...