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Inorganic Blind Sample Project (IBSP)

Tools for Laboratory Evaluation Process for NWQL Data

NEW Updated January 2024

This page is useful for obtaining charts and data specific to NWQL performance for use in the Laboratory Evaluation Process.

External performance-assessment data for the National Water Quality Laboratory inorganic and physical analytes are available from the Inorganic Blind Sample Project for laboratory evaluations. The links provided below will take you to PDFs containing control charts (analysis dates October 2019 through September 2023) that show performance-assessment data from double-blind samples for all analytes in the selected analytical group. PDFs are available for blind samples—both non-blank and blank. The files are updated annually. The next update will be in January 2025 to allow the NWQL time to analyze and process results for all FY24 inorganic samples. A custom data pull can easily be done prior to that time if needed. For custom requests please contact the IBSP Project Chief.

If you prefer to work with the performance data directly, the data set for the performance samples—both non-blank and blank—are available via the XLSX output link (last link shown below). Non-blank and blank data are within one file separated into separate worksheets.

For more specific trouble-shooting tools or a longer period of performance data than is available on this page, check out the historical charts and data sets here or contact the IBSP Project Chief. Non-blind, on-line QC data can be accessed on the NWQL's on-line QC data web-page here.

Please note: the charts and data that you might secure from this U.S. Geological Survey (USGS) web page (identified as "IBSP") have not received official USGS approval and as such are provisional and subject to revision. The charts and data are released on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from its authorized or unauthorized use.

Performance charts for non-blank, blind samples. (Charts updated annually.)

Nutrients Trace Elements Major Ions, Silica, Physical Properties, Other All Parameters  

Performance charts for blind blank samples. (Charts updated annually.)

Nutrients Trace Elements Major Ions, Silica, Physical Properties, Other All Parameters  

XLXS output: File contains all parameter types and both non-blank and blind blank performance data.

Performance Data for All Parameters (.xlsx)    


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