The driver of a concrete truck with a prior drug use history showed up late for work, behaved erratically at a customer’s site and had a traffic accident. Co-workers said he wasn’t fit to drive before the accident. A supervisor drove him home. The employer told him he couldn’t return to work until he passed a drug test. But he refused to take one. The arbitrator ruled that the employer had reasonable cause to require the worker to submit to drug testing before returning to work in his safety-sensitive position [Dufferin Concrete v. Teamsters, Local 230 (Luck Grievance),  O.L.A.A. No. 654, Dec. 15, 2010].