Chapter A6. Section 6.5. Reduction-Oxidation Potential (Electrode Method)

Techniques of Water-Resources Investigations 09-A6.5
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Reduction-oxidation (redox) potential--also referred to as Eh--is a measure of the equilibrium potential, relative to the standard hydrogen electrode, developed at the interface between a noble metal electrode and an aqueous solution containing electroactive chemical species. Measurements of Eh are used to evaluate geochemical speciation models, and Eh data can provide insights on the evolution and status of water chemistry in an aqueous system. Nevertheless, the measurement is fraught with inherent interferences and limitations that must be understood and considered to determine applicability to the aqueous system being studied. For this reason, Eh determination is not one of the field parameters routinely measured by the U.S. Geological Survey (USGS). This section of the National Field Manual (NFM) describes the equipment and procedures needed to measure Eh in water using a platinum electrode. Guidance as to the limitations and interpretation of Eh measurement also is included. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be announced on the USGS Home Page on the World Wide Web under 'New Publications of the U.S. Geological Survey.'

Suggested Citation

Nordstrom, D.K., and Wilde, F.D., 2005, Reduction-oxidation potential (electrode method) (ver. 1.2, September 2005): U.S. Geological Survey Techniques of Water-Resources Investigations, book 9; chap. 6.5,

Table of Contents

  • Reduction-Oxidation Potential (Electrode Method)
  • Illustrations
Publication type Report
Publication Subtype USGS Numbered Series
Title Chapter A6. Section 6.5. Reduction-Oxidation Potential (Electrode Method)
Series title Techniques of Water-Resources Investigations
Series number 09-A6.5
DOI 10.3133/twri09A6.5
Edition Version 1.2
Year Published 2005
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) U.S. Geological Survey
Description 22 p.
Larger Work Type Report
Larger Work Subtype USGS Numbered Series
Larger Work Title National Field Manual for the Collection of Water-Quality Data. U.S. Geological Survey Techniques of Water-Resources Investigations, Book 9
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