A passenger's requirement for accessibility, comprising one or more USER NEEDs, e.g., that he is unable to navigate stairs, or lifts, or has visual or auditory impairments.<br/>NOTE: PASSENGER ACCESSIBILITY NEEDS can be used to derive an accessibility constraint for the passenger, allowing the computation of paths for passengers with specifically constrained mobility such as in Wheelchair, No Lifts, No Stairs, etc.<br/><br/>
