External Quality Assurance Programs

Proficiency Testing Program

What is Proficiency Testing?

Proficiency Testing (PT) is the testing of samples sent to laboratories by an accredited provider to evaluate the ability of a laboratory to produce a test result within acceptable performance criteria. The concentration of the analyte(s) in the sample is unknown to the laboratory at the time of testing. PT is important because it is a tool the laboratory uses to verify the accuracy and reliability of its testing. Review of the PT results by the laboratory alerts the staff to areas of testing that are not acceptable. The PT results also are indicators to prevent small shifts or trends that over time would impact the quality performance of the analysis. PT samples are also known as performance evaluation samples or reference samples.

Truesdail participates annually, at a minimum, and throughout the year in Environmental PT programs with a leading third-party PT provider (Phenova), that is both ISO/IEC 17025 and Guide 34 accredited. Our laboratory successfully completes PT studies for a variety of matrices including drinking water (water supply), wastewater (water pollution) and soils (hazardous waste) samples with a greater than 97% pass rate on the initial testing. Truesdail participates in PT testing for all of its certified analysis, including:

  • Metals
  • Volatile Organics
  • Semi-Volatile Organics
  • Ion Chromatography
  • Microbiological Testing
  • Wet & General Chemistry

External Assessments

External Quality Assessments are an independent audit from an outside organization that provides a statement of conformance to quality standards. External assessments provide objective evidence of laboratory competence and quality management systems.

Truesdail is distinguished in having ISO/IEC 17025 accreditation (Laboratory Competency/Quality Management System) through ANAB, California ELAP accreditation, approvals with SCAQMD, and handling of nuclear related materials through NIAC. Truesdail is subject to external assessments from each of these regulatory bodies to ensure compliance of our quality system relating to our analysis. We are highly confident in our competency and with our paradigm of “Continual Improvement”, we often go above and beyond the requirements of regulatory agencies. These external audits are verification that our quality systems are meeting or exceeding the requirements. These external assessment serve as a unique source of information that is unobtainable in other ways and are a valuable tool our quality ‘continual improvement’ process.