Data Quality - QA/QC

Field Quality Control Sample - Trip Spike
Trip Spikes A sample prepared by the laboratory that is fortified with a known concentration of target analytes.  This sample is shipped along with cont...
Tue, 7 May, 2019 at 2:09 PM
Field Quality Control Sample - Field Blank
Field Blanks Supplied by the laboratory and prepared in the field by filling container with analyte free water. Frequency and Purpose 1 per set of env...
Thu, 20 Dec, 2018 at 7:47 AM
Field Quality Control Sample - Blind Known
A purchased CRM / LCS or a sample previously analysed by an accredited laboratory multiple time, is submitted to the laboratory blind (without laboratory kn...
Thu, 20 Dec, 2018 at 7:55 AM
Quality Control - Blanks
Sample/Field Blanks and Laboratory Blanks are treated and processed in the same manner as the samples they are submitted with.  Within the laboratory, they ...
Thu, 19 Dec, 2019 at 3:07 PM
My field duplicate results do not match the sample results, why?
Field duplicates can either be submitted blind or known to the lab.  With a field duplicate a second sample is collected at the same time and location in se...
Mon, 14 Jan, 2019 at 3:01 PM
I have unexpected positive results. What should I review?
There are a number of quality measures you can investigate on your report when reviewing"positive hits" or detected concentrations of unexpected t...
Wed, 30 Jan, 2019 at 1:41 PM
What does the “Qualifying ion outside of acceptance criteria. Results are tentatively identified and potentially biased high” comment mean?
A qualifier ion (a less abundant ion of a target compound that is typically always present in a known ratio to the target), is most often used when utilizin...
Mon, 11 Feb, 2019 at 2:25 PM
Why do the laboratory duplicates not match?
Laboratory duplicates (lab dup) are necessary and typical quality control sample used for all analyses.  A lab dup in a batch of 20 samples or less is r...
Tue, 12 Feb, 2019 at 12:38 PM
EPA Data Qualifiers used for HRMS results.
In some situations data will be reported with a qualifier. The following is a listing of EPA Data Qualifiers used for HRMS results. These are used to fl...
Wed, 20 Feb, 2019 at 8:58 AM
BOD note "Detection limit raised based on sample volume used for analysis"
The note "Detection limit raised based on sample volume used for analysis." doesn't mean that we didn't have enough volume, rather it m...
Mon, 10 Jan, 2022 at 7:59 PM