Quality Assurance

Our staff are committed to providing high quality data to our customers. A comprehensive quality assurance (QA) program ensures this with the following:

  • Adherence to documented referenced standard operating procedures (SOPs)
  • Quality control (QC) samples run with each sample batch: blanks, duplicates, certified external reference standards, and/or matrix spike samples (as appropriate)
  • Instrument monitoring using instrument blanks and certified check standards
  • Scheduled balance calibrations using N.I.S.T. certified Class I calibrated weights
  • Corrective Action reporting for continuous improvement

Samples are analyzed using standard methods as described in the Analytical Methods section. Documented SOPs are followed to ensure consistency and provide analytical reliability over time.

Approximately 10% of samples are duplicate-tested at no cost to the client as part of our QA program. Typically one Check Standard and one External Reference Standard are run with each set of analyses. The QC results are included in the final report.

A reagent blank is analyzed with every set of samples that are extracted or digested. This blank includes all reagents that are used in the analytical process and is carried through the entire process, including extraction and filtering or digestion.

Our laboratory has implemented a program for the documentation of Corrective Actions when addressing customer complaints. In the rare instance where data veracity is questioned (e.g. high duplicate relative percent difference, QC checks out of control), the laboratory follows a Corrective Action procedure whereby the sample analysis trail is investigated from start to finish in order to ascertain whether an error occurred, why it happened, and what corrective actions must be instituted so the error does not reoccur. The customer receives a signed copy of the Corrective Action Report if requested, along with no cost re-analysis if warranted.