"THC concentration" means nanograms of delta-9 tetrahydrocannabinol per milliliter of a person's whole blood. THC concentration does not include measurement of the metabolite THC-COOH, also known as carboxy-THC.
RCW 46.04.586
Intent- 2013 c 3 (Initiative Measure No. 502): See note following RCW 69.50.101.