As used in §§ 46.2-341.26:2 through 46.2-341.26:11, unless the context clearly indicates otherwise: The phrase “alcohol or drug” means alcohol, drug or drugs, or any combination of alcohol and a drug or drugs. The phrase “blood or breath” means either or both. “Chief police officer” means the sheriff in any county not having a chief of police, the chief of police of any county having a chief of police, the chief of police of the city, or the sergeant or chief of police of the town in which the charge will be heard, or their authorized representatives. “Department” means the Department of Forensic Science. “Director” means the Director of the Department of Forensic Science.