Version History for U.S. Geological Survey Techniques and Methods 9-A6.8

By U.S. Geological Survey

Use of Multiparameter Instruments for Routine Field Measurements
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First posted online August 2007 as Techniques of Water-Resources Investigations (TWRI), book 9, chapter A6.8, version 1.0

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Revised and reposted March 2012 as version 1.1

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Revised and reposted November 28, 2023 as Techniques and Methods, book 9, chapter A6.8

U.S. Geological Survey, 2023, Use of Multiparameter Instruments for Routine Measurements: U.S. Geological Survey Techniques and Methods, book 9, chap. A6.8, XX p., https://doi.org/10.3133/tm9A6.8. [Supersedes USGS Techniques of Water-Resources Investigations, book 9, chap. A6.8, version 1.1.]

The personal authors were changed to the agency, U.S. Geological Survey.
The report series was changed as indicated above.
The layout was changed to match the current style and format of a USGS series report, and the text was set in two columns. A front cover, back cover, title page, and back-of-title page were added and show the following: the change of series (to a T&M), the change in authorship, and a statement that this 2023 release of chapter A6.8 in the T&M supersedes TWRI, book 9, chapter A6.8, version 1.1.

Substantive changes made in book 9, chapter A6.8, in 2023 are summarized below:
Calibration procedures were generalized with references made to NFM field parameter chapters A6.1 through 6.7 for specific procedures.
The calibration order for parameters was reordered to reflect an emphasis on the importance of zero checks for dissolved oxygen.
Stabilization criteria for specific conductance was changed to match NFM A6.3 Specific Conductance.
Stabilization criteria for pH was changed to match NFM A6.4 Measurement of pH.