(a) Vehicles shall be parked only in those portions of rest or parking areas or scenic overlooks designated for parking and in accordance with the sign or striping scheme found therein.

(b) In no event shall a vehicle be parked in such a manner as to block ingress or egress to or from a rest or parking area or scenic overlook, or to prevent the free movement of another vehicle therein.

(c) Parking of vehicles for longer than three hours during the hours of darkness is not permitted in any rest or parking area or scenic overlook; provided, however, that a commercial motor vehicle, as defined in section 820.1 of this Title, may, except as provided otherwise by the Department of Transportation by the posting of signs, remain motionless at such an area for up to 10 hours if the commercial vehicle driver is present and is required to use this period as off duty or sleeper berth time to allow rest in accordance with Federal or State motor carrier safety hours of service regulations.

(d) Vehicles shall not be left unattended in rest or parking areas or scenic overlooks, unless the owner, operator or a passenger thereof is within the rest or parking area or scenic overlook or is on adjacent land to which access is permitted. However, in the case of mechanical failure, a vehicle may be left in a rest or parking area or scenic overlook with a notice attached to the windshield setting forth the name and address of the owner or operator, the nature of the mechanical failure, and the date and time when the owner or operator left the rest or parking area or scenic overlook.

(e) In no event shall any vehicle be parked or left in a rest or parking area or a scenic overlook for more than 24 hours.