Each ambulance shall carry the following standard equipment for carrying patients: One ambulance stretcher that: Is adjustable in height, Permits the elevation of the upper body, Has a mattress covered with nonabsorbent material free from defects, such as rips and tears, Has safety straps to secure the patient in accordance with the manufacturer's recommendations, and Has a stretcher-mounted IV pole or equivalent; and One folding stair chair capable of negotiating narrow hallways or stairways.