ASTM D5462-21

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

SIGNIFICANCE AND USE
5.1 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.  
5.2 Feedwater chemistry guidelines for high-pressure boilers generally require specific feedwater DO concentrations: 5 μg/L or less for reducing all volatile treatment [AVT(R)]; 5–10 μg/L for oxidizing all volatile treatment [AVT(O)]; 50–200 μg/L for oxygenated treatment [OT] (3).  
5.3 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. The values given in parentheses after SI units are provided for information only and are not considered 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazards statements, see 6.5.  
1.4 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.

General Information

• Status: Published
• Publication Date: 31-May-2021
• 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

Standards Content (Sample)

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: D5462 − 21
Standard Test 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 D3370 Practices for Sampling Water from Flowing Process
Streams
1.1 This test method covers the on-line determination of
D3864 Guide for On-Line Monitoring Systems for Water
dissolved oxygen (DO) in water samples primarily in ranges
Analysis
from 0 to 500 µg/L(ppb), although higher ranges may be used
for calibration. On-line instrumentation is used for continuous
3. Terminology
measurements of DO in samples that are brought through
sample lines and conditioned from high-temperature and high-
3.1 Definitions:
pressure sources when necessary.
3.1.1 For definitions of terms used in this standard, refer to
Terminology D1129.
1.2 The values stated in SI units are to be regarded as
standard. The values given in parentheses after SI units are
3.2 Definitions of Terms Specific to This Standard:
provided for information only and are not considered standard.
3.2.1 diffusion-type probes, n—galvanic or polarographic
1.3 This standard does not purport to address all of the sensorsthatdependonthecontinuousinfluxofoxygenthrough
safety concerns, if any, associated with its use. It is the the membrane to develop the electrical signal.
responsibility of the user of this standard to establish appro-
3.2.2 equilibrium-type probes, n—modified polarographic
priate safety, health, and environmental practices and deter-
sensing probes that have a negligible influx of oxygen through
mine the applicability of regulatory limitations prior to use.
the membrane except during changes of sample DO concen-
For specific hazards statements, see 6.5.
tration.
1.4 This international standard was developed in accor-
3.2.2.1 Discussion—Oxygen consumption and regeneration
dance with internationally recognized principles on standard-
balance each other within the probes under stable conditions,
ization established in the Decision on Principles for the
and the net flux through the membrane is insignificant.
Development of International Standards, Guides and Recom-
3.2.3 galvanic systems, n—sensing probes and measuring
mendations issued by the World Trade Organization Technical
instruments that develop an electrical current from two elec-
Barriers to Trade (TBT) Committee.
trodes inside the probe from which the final measurement is
derived.
2. Referenced Documents
2
3.2.4 partialpressure(ofoxygen),n—thevolumefractionof
2.1 ASTM Standards:
oxygen multiplied by the total pressure.
D1066 Practice for Sampling Steam
D1129 Terminology Relating to Water 3.2.4.1 Discussion—The partial pressure of oxygen is the
actual parameter detected by DO probes, whether in air or
D1193 Specification for Reagent Water
D2777 Practice for Determination of Precision and Bias of dissolved in water.
Applicable Test Methods of Committee D19 on Water
3.2.5 polarographic systems, n—sensing probes and mea-
suring instruments that include circuitry to control the operat-
ing voltage of the system, usually using a third (reference)
1
This test method is under the jurisdiction of ASTM Committee D19 on Water
electrode in the probe.
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.
4. Summary of Test Method
Current edition approved June 1, 2021. Published June 2021. Originally
4.1 Dissolved oxygen is measured by means of an electro-
approved in 1993. Last previous edition approved in 2013 as D5462 – 13. DOI:
10.1520/D5462-21.
chemical cell separated from the sample by a gas-permeable
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
membrane. Behind the membrane and inside the probe, elec-
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
trodes immersed in an electrolyte develop an electrical current
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. proportional to the oxygen partial pressure of the sample.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D5462 − 21
4.2 The partial pressure signal is temperature compensated 6. Interfer
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM 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 − 13 D5462 − 21
Standard Test 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
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 The values
given in parentheses after SI units are provided for information only and are not considered 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. For specific hazards statements, see 6.5.
1.4 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D1066 Practice for Sampling Steam
D1129 Terminology Relating to Water
D1193 Specification for Reagent Water
D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
D3370 Practices for Sampling Water from Flowing Process Streams
D3864 Guide for On-Line Monitoring Systems for Water Analysis
3. Terminology
3.1 Definitions—Definitions: For definitions of terms used in this test method, refer to Terminology D1129.
3.1.1 For definitions of terms used in this standard, refer to Terminology D1129.
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 June 15, 2013June 1, 2021. Published July 2013June 2021. Originally approved in 1993. Last previous edition approved in 20082013 as
D5462 – 08.D5462 – 13. DOI: 10.1520/D5462-13.10.1520/D5462-21.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’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 − 21
3.2 Definitions of Terms Specific to This Standard:
3.2.1 diffusion-type probes, n—galvanic or polarographic sensors that depend on the continuous influx of oxygen through the
membrane to develop the electrical signal.
3.2.2 equilibrium-type probes, n—modified polarographic sensing probes that have a negligible influx of oxygen through the
membrane except during changes of sample DO concentration.
3.2.2.1 Discussion—
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, n—sensing probes and measuring instruments that develop an electrical current from two electrodes inside
the probe from which the final measurement is derived.
3.2.4 partial pressure (of oxygen), n—the volume fraction of oxygen multiplied by the total pressure.
3.2.4.1 Discussion—
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, n—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.
4. Summary of Test Method
4.1 Dissolved oxygen is measur
...