Emergency access shall be provided by way of paved streets, alleys, hard surface and/or marked stabilized turf driveways along at least three of four sides of all buildings that have a width or length exceeding 250 feet. No emergency access shall be located more than 200 feet from the building it services. If emergency access requirements are satisfied by constructing a sidewalk, such sidewalk shall be at least 10 feet wide and shall have a minimum radius of 50 feet at turns and intersections and be able to support an emergency vehicle.