(1) Driving Relevant Functional Impairment means observed or identified evidence of any functional impairment that limits a person's physical activity, or sensory or motor functions, or physical ability, or visual acuity or visual-spatial processing necessary to exercise safe control at all times over a motor vehicle, including the strength, flexibility, reflexes, sensory perception and physical coordination necessary to maintain safe control of a vehicle on the road.

1. (a) Evidence of impaired strength includes but is not limited to:

   1. 1. the inability or diminished capacity to consistently maintain a firm grasp on or manipulate a steering wheel or driving hand controls; or
   2. 2. the inability or diminished capacity to apply consistent pressure with legs and feet to vehicle foot controls or manipulate or release vehicle foot controls; or,
   3. 3. weakness or paralysis of muscles affecting the ability to consistently maintain sitting balance or exercise safe control of a vehicle for prolonged distances.
2. (b) Evidence of impaired flexibility includes but is not limited to rigidity or limited range of mobility in neck, torso, arms, legs or joints.