ASME A90.1-2015 pdf – Safety Standard for Belt Manlifts.
5.6.4 Prohibition of Handhold Without Steps. No
handhold shall be provided without a corresponding step. If a handhold is removed permanently or temporarily, the corresponding step and handhold for the opposite direction of travel shall be removed before the manlift is again placed in service.
5.6.5 Surfaces. All handholds shall be the closed type and in high contrast color with the belt.
5.7 Safety Stops
5.7.1 Upper Limit Safety Stops. Three separate automatic safety stops shall be provided to shut off the power and apply the brake when a loaded step passes the top landing. Two of these shall consist of split-rail safety stops or in-track equivalent safety stops located on opposite guide rails, mechanically operated by the step. These two safety stops shall function so that the manHft will be stopped before the loaded step has reached a point 24 in. (610 mm) above the top landing. The third automatic stop device shall consist of one of the following:
(a) an electronic device
NOTE: A time delay switch may be required as part of an electronic device installation to permit passage of empty steps.
(b) a switch actuated by a lever, bar, or plate to be placed at the top pulley on the up-side, and shall be at a 45-deg angle with a maximum of 1-in. (25-mm) clearance from a passing step. The actuating bar shall be hinged or of a breakaway type so as not to create a hazard.
5) 5.7.2 Lower Limit Safety Stops. Two separate automatic safety stops shall be provided to shut off the electric power and apply the brake when a loaded step passes the bottom landing (refer to para. 4.6.2). One of these devices shall activate while the step is still in the horizontal position. Automatic safety stops may consist of the following:
(a) a split-rail or equivalent safety stop located on the opposite guide rail
(b) an electronic device, or
(c) a treadle safety stop
No lower limit safety stops are required for a permanently installed riser, provided that it is 10 in. (250 mm) in height or less from the floor.
5.7.3 Manual Reset Location. After the manlift has been stopped by an automatic safety stop, it shall be necessary to reset the electrical control circuit manually. A manual reset shall always be located at the top landing. When safety stops are provided at the bottom landing, a reset button shall also be included (at the bottom landing). The reset shall be so located that a person resetting it shall have a clear view of both the up- and down-runs of the man lift. It shall not be possible to reset the electrical control circuit from any step. Manual resets are permissible at top and bottom landings only.
5.5.2 Width. The width of the step or platform shall be not less than the width of the belt to which it is attached.
5.5.3 Distance Between Steps. The distance between steps shall be equally spaced and not less than 16 ft (4.8 m), measured from the upper surface of one step to the upper surface of the next step above it.
5.5.4 Angle of Step. The surface of the step shall make approximately a right angle with the up- and down-runs of the belt and shall travel in the approximate horizontal position with the up- and down-runs of the belt.
5.5.5 Surfaces. Each step shall be protected with a nonslip tread or surface.
5.5.6 Strength of Step Supports. When subjected to a load of 400 lb (180 kg mass) applied at the approximate center of the step, step frames, or supports and their guides shall be of adequate strength to prevent
(a) the disengagement of any step roller
(b) any appreciable misalignment
(c) any visible deformation of the steps or their supports
5.5.7 Steps. Steps shall be attached using elevator bolts with locking washers and nuts or locking nuts.
5.5.8 Prohibition of Steps Without Handholds. No step shall be provided unless there is a corresponding handhold above and below it meeting the requirements of para. 5.6. If a step is removed for any reason, the handholds immediately above and below it shall be removed before the manlift is again placed in service.
5.5.9 Color. Each step or step surface shall be in high contrast color with the belt.
5.6 Handholds
5.6.1 Location. Handholds attached to the belt shall be provided and so installed that they are not less than 4 ft (1.2 m) nor more than 4 ft 8 in. (1 420 mm) above the step tread and centered on the belt (see Fig. 9). These handholds shall be so located as to be available on both the up- and down-runs of the belt. All handholds on any given manlift should be located the same distance above the step treads.