Chapter A6.2. Dissolved Oxygen

Techniques and Methods 9-A6.2



The “National Field Manual for the Collection of Water-Quality Data” (NFM) provides guidelines and procedures for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation’s surface water and groundwater resources. This chapter, NFM A6.2, provides guidance and protocols for the measurement of dissolved oxygen, which include the scientific basis of the measurement, selection and maintenance of equipment, calibration, troubleshooting, and procedures for measurement and reporting. It updates and supersedes USGS Techniques of Water-Resources Investigations, book 9, chapter A6.2, version 3.0, by Stewart A, Rounds, Franceska D. Wilde, and George F. Ritz. Dissolved oxygen is routinely measured when water samples are collected, is often continually measured at USGS streamgages, and is a parameter regularly measured during laboratory and field experiments. The field method for measuring dissolved oxygen described in this chapter is applicable to most natural waters.

Before 2017, the USGS NFM chapters were released in the USGS Techniques of Water-Resources Investigations series. Effective in 2018, new and revised NFM chapters are being released in the USGS Techniques and Methods series; this series change does not affect the content and format of the NFM. More information is in the general introduction to the NFM (USGS Techniques and Methods, book 9, chapter A0—U.S. Geological Survey, 2018) at The authoritative current versions of NFM chapters are available in the USGS Publications Warehouse at Comments, questions, and suggestions related to the NFM can be addressed to

Suggested Citation

U.S. Geological Survey, 2020, Dissolved oxygen: U.S. Geological Survey Techniques and Methods, book 9, chap. A6.2, 33 p., [Supersedes USGS Techniques of Water-Resources Investigations, book 9, chap. A6.2, version 3.0.]

ISSN: 2328-7055 (online)

Table of Contents

  • Abstract
  • 1.0 Introduction
  • 2.0 Optical (Luminescence) Sensor Method
  • 3.0 Spectrophotometric (Rhodazine D and Indigo Carmine) Methods
  • 4.0 Reporting
  • 5.0 Correction Factors for Oxygen Solubility and Salinity
  • Acknowledgments
  • References Cited
  • Appendix 1. Example comparison between spectrophotometric and optical dissolved-oxygen meter data
Publication type Report
Publication Subtype USGS Numbered Series
Title Chapter A6.2. Dissolved oxygen
Series title Techniques and Methods
Series number 9-A6.2
DOI 10.3133/tm9A6.2
Year Published 2020
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) WMA - Observing Systems Division
Description vi, 33 p.
Larger Work Type Report
Larger Work Subtype USGS Numbered Series
Larger Work Title Section A: National field manual for the collection of water-quality data in Book 9: Handbooks for water-resources investigations
Online Only (Y/N) Y
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details