Section 309.005 - Driving Relevant Impairments(A)Driving Relevant Cognitive Impairment means a cognitive impairment that limits a person's ability to sustain attention, avoid distraction, understand the immediate driving context, and refrain from impulsive responding; to identify problems that arise in a driving context and make appropriate decisions to address those problems necessary to the safe operation of a motor vehicle.(B) 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 visuospatial 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) Evidence of impaired strength includes but is not limited to: (a) Inability or diminished capacity to consistently maintain a firm grasp on or manipulate a steering wheel or driving hand controls; or,(b) Inability or diminished capacity to apply consistent pressure with legs and feet to vehicle foot controls or manipulate or release vehicle foot controls; or,(c) Weakness or paralysis of muscles affecting ability to consistently maintain sitting balance or exercise safe control of a vehicle for prolonged distances.(2) Evidence of impaired flexibility includes but is not limited to rigidity or limited range of mobility in neck, torso, arms, legs or joints.(3) Standards regarding vision functionality or impairment are set forth in 540 CMR 24.05: Visual Standards and Procedures.(4) Standards regarding episodic seizure and loss of consciousness and six-month episode-free requirements are set forth in 540 CMR 24.06: Seizure and Loss of Consciousness Standards and Procedures.(5) Standards regarding cardiovascular and respiratory disease and functional status are set forth in 540 CMR 24.07: Cardiovascular and Respiratory Disease Standards and Procedures.(6) Standards regarding musculo-skeletal conditions and functional status for people unable to perform self-care are set forth in 540 CMR 24.08: Arthritis Disease Standards and Procedures.(C) A driving relevant impairment is one that is not based solely on age or solely on the diagnosis of a medical condition or cognitive or functional impairment, but is based on observations or evidence of the actual effect of that condition or impairment on the person's ability to safely operate a motor vehicle.(D) A driving relevant impairment is one that cannot be sufficiently corrected or controlled by medication, therapy, surgery; adaptive equipment; or by driving device or technique.