Methods and systems using one or more expert systems to screen equipment operators for impairments, such as intoxication, physical impairment, medical impairment, or emotional impairment, to selectively test the equipment operators and control the equipment (e.g., automobiles, trucks, industrial vehicles, public transportation vehicles, such as buses, subways, trains, planes, and ships, and dangerous machinery in general) if impairment of the equipment operator is determined. One embodiment is a method to screen an equipment operator for intoxication, using one or more expert systems. A second embodiment is a method to screen an equipment operator for impairment, such as intoxication, physical impairment, medical impairment, or emotional impairment, using one or more expert systems. A third embodiment is an equipment operator screening system to determine impairment, such as intoxication, physical impairment, medical impairment, or emotional impairment, using one or more expert systems.