Washington Administrative Code
Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508)
Chapter 173-50 - Accreditation of environmental laboratories
Section 173-50-061 - Required quality control practices
Current through Register Vol. 24-06, March 15, 2024
Laboratories must comply with the following quality control practices:
(1) Have a dedicated SOP for each method listed on their current Washington scope of accreditation.
(2) For parameters where a multilevel calibration is necessary:
(3) For parameters that require a limit of quantitation and the method does not specify any requirements, laboratories must analyze a standard at their limit of quantitation at least annually. This standard must be between 50 and 150 percent of the true value. This applies to the following instrumentation technologies:
(4) Matrix spikes are required as specified by the method. Matrix spikes that do not meet their acceptance criteria must be documented for regulated parameters under the federal Safe Drinking Water Act and Clean Water Act. The lab must take corrective action if specified by the method.
(5) Unless the method specifies otherwise, laboratory control samples must include all analytes of interest in the respective analysis. Matrix spikes should include all analytes of interest in the respective analysis.
(6) For compliance monitoring samples, if a laboratory control sample is outside of its acceptance criteria for a parameter(s), the data for that parameter(s) should only be reported if the laboratory can demonstrate:
(7) Documented resolution of spectral interferences is required for ICP-OES.