Method performance criteria.
(1) Accredited labs may reference samples for testing by subcontracting fields of testing to another accredited laboratory.
(2) Laboratories must maintain the integrity of the sample by testing samples on an "as is" or "as received" basis before sample prep unless otherwise specified in rules.
(3) Laboratories may use historical calibrations for high complexity testing as long as it is supported by analytical data through quality control results. Historical calibrations cannot extend past 30 days.
(4) The samples fail quality control testing if the results exceed the limits indicated in chapter
314-55 WAC.
(5) Sample results are positive for the analyte being tested if their results are greater than or equal to the decision point or cutoff limits as indicated in chapter
314-55 WAC.
(6) Sample results are to be reported out in the number of digits and units of measure described in chapter
314-55 WAC.
(7) Laboratories may be accredited to conduct the following fields of testing:
Field of Testing | Level of Complexity |
water activity | low |
cannabinoid concentration analysis | high |
foreign matter inspection | low |
microbiological testing | |
| culture method | moderate |
| immunoassay method | moderate |
| polymerase chain reaction (PCR) method | high |
residual solvent testing | high |
mycotoxin testing | |
| enzyme-linked immunosorbent assay (ELISA) method | moderate |
| liquid chromatography with tandem mass spectrometry (LC-MS/MS) method | high |
pesticide testing | high |
heavy metals testing | high |
[Statutory Authority: RCW
15.150.030 and 2022 c 135. WSR 24-09-079, § 16-309-140, filed 4/17/24, effective 5/18/24.]