WAC 16-309-160. Cannabinoid concentration analysis

(1) Cannabinoid concentration analysis, previously known as potency, is intended to quantitate and accurately report cannabinoids above the lower limit of quantitation as described in chapter 314-55 WAC. (2) Laboratories must use a method approved by the department to analyze cannabinoids. (3) Laboratories must limit batch size to 20 samples in a preparation batch not including quality controls. (4) ICV, CCV, and surrogate must meet a minimum of 80-120 percent recovery for each analyte. (5) LCS and matrix spike samples must meet a minimum of 70-130 percent recovery for each analyte. (6) Sample and matrix spike duplicates must have a relative percent difference (RPD) value of less than 20 percent. (7) Chromatographic performance must be described in method and must include, but is not limited to, the following criteria: (a) Tailing factor less than 2.0; (b) Column performance resolution greater than 1.0; (c) Retention time shift less than two percent.