ASME A18.1-2011 pdf – Safety Standard for Platform Lifts and Stairway Chairlifts.
It shall be operable only when the passenger restraining arm at the nonboarding end of the platform is in its locked guarding position. Retractable ramps shall be mechanically locked and monitored by an electric contact, which shall stop the movement of the platform within 50 mm (2 in.) of travel away from the landing if the ramps have failed to rise to their elevated position. Retractable ramps, in their guarding position, shall withstand, without permanent deformation, a force of 550 N (125 lbf) applied on any 100 mm (4 in.) by 100 mm (4 in.) area. This force shall not cause the height of the ramp, at any point in its length, to be less than 150 mm (6 in.) measured vertically from the surface of the platform floor.
3.6.8.2.4 The platform shall be provided with retractable passenger restraining arms conforming to the following:
(a) The arms shall be located above the perimeter of the platform floor at not less than 800 mm (32 in.) or greater than 1 000 mm (38 in.). Gaps between the adjacent ends of arm sections shall not exceed 100 mm (4 in.) when the arms are in their guarding positions.
(b) The arms shall be of smooth construction with all edges rounded. They shall not be permanently deformed when a force of 300 N (66 lbf) is applied on any point along the length of the arms in any direction. In addition, they shall not be permanently deformed when a force of 1 000 N (225 lbf) is applied in the horizontal direction along the center line of the platform.
(c) The arms shall be provided in independent sections. At landings, the retractable ramp and arm at the boarding end of the platform shall be operable only when the arm at the nonboarding end of the platform is in its locked guarding position.
(d) Each retractable arm shall be mechanically locked and monitored by an electric contact, which shall stop the movement of the platform within 50 mm (2 in.) of travel away from any landing if the arm is not in its locked guarding position. Means shall be provided to manually unlock the retractable arms for emergency evacuation purposes. The unlocking mechanism shall not be readily accessible to the passenger.
(e) Where the retractable arms are power operated, control shall be by means of a continuous pressure device. The closing speed shall not exceed 0.3 rn/s (1 ft/sec) as measured at the fastest point. The force necessary to prevent closing of power-operated arms shall not exceed 140 N (30 lbf) as measured from rest at the midpoint across the arm at the boarding end of the platform. The arms may operate in the direction away from an obstruction.
3.6.9 Obstruction Devices. The upward and downward facing edges of the platform floor and the entire underside shall be equipped with obstruction devices. The force required to operate the devices shall not exceed 70 N (15 lbf). The obstruction devices shall stop the platform lift from traveling in the direction of the obstruction within a distance of 50 mm (2 in.). The platform lift shall be permitted to operate in the direction away from the obstruction.
The underside obstruction device shall stop the platform lift only when the platform lift is obstructed while traveling in the down direction.
3.6.10 The lift shall be provided with a folding seat and seatbelt with a rated load of not less than 115 kg (250 lb).
3.7 Capacity, Load, Speed, and Angle of Inclination
3.7.1 Limitations of Capacity, Load, and Speed. The (
capacity shall be one person. The rated load shall be not less than 200 kg (450 Ib) and not greater than 340 kg (750 ib). Platforms with a floor area greater than 1.4 m2 (15 ft2) shall have a rated load of 340 kg (750 ib). The lift shall be capable of sustaining and lowering a load as specified in Fig. 9.7. The rated speed measured along the incline shall not exceed 0.15 rn/s (30 ft/mm).
3.7.2 Limitation of Angle. No lift shall be installed to operate on an incline greater than 45 deg as measured on the mean.
3.7.3 Capacity Plate. A capacity plate stating the rated load in pounds shall be furnished by the manufacturer and fastened in a conspicuous place on the lift. Letters and numbers shall be not less than 6 mm (0.25 in.) in height.