RCW 46.25.110: Driving with alcohol or THC in system.

(1) Notwithstanding any other provision of Title 46 RCW, a person may not drive, operate, or be in physical control of a commercial motor vehicle while having alcohol or THC in his or her system.

(2) Law enforcement or appropriate officials shall issue an out-of-service order valid for twenty-four hours against a person who drives, operates, or is in physical control of a commercial motor vehicle while having alcohol or THC in his or her system or who refuses to take a test to determine his or her alcohol content or THC concentration as provided by RCW 46.25.120.