Subchapter K. DUMBWAITERS

§ 7.341. Applicability.

 (a)  New installations. This subchapter applies to all dumbwaiters except handpower dumbwaiters, the car floor of which is less than three square feet in area with a travel not over 12 feet and a rated capacity of not over 75 pounds.

 (b)  Existing installations. This subchapter applies to all dumbwaiters except handpower dumbwaiters, the car floor of which is less than three square feet in area.

 (a)  Fire-resistive enclosures shall be provided as follows:

   (1)  New installations. The shaftways of dumbwaiters installed subsequent to December 15, 1924, with car travel of over two stories shall be of fire-resistive construction.

   (2)  Existing installations. The shaftways of dumbwaiters erected after July 1, 1916, and prior to December 15, 1924, shall be constructed of fire-resistive material as follows:

     (i)   In buildings of frame construction where car travel is over two stories.

     (ii)   In buildings of ordinary construction where car travel is over three stories.

     (iii)   In buildings of fire-resistive construction where car travel is over four stories.

 (b)  In each case where fire-resistive construction is not required in both existing and new installations, shaftways shall be enclosed on all sides not used for loading or unloading from the floor to a height of at least 6 feet. On sides used for loading or unloading, the enclosure shall extend from the floor to the ceiling, except the space required for doors or gates. If, in the judgment of the Department, such shaftways present a fire hazard they shall be entirely enclosed with fire-resistive material.

 (c)  Ordinary enclosures for dumbwaiter shaftways may be of wire mesh, not less than No. 10 standard steel wire gauge (0.135 inch) or expanded metal, not less than No. 13 U.S. gauge (0.09375 inch). Openings in the mesh shall not exceed 1 1/2 inches. The open spaces in grillework shall not be in excess of 1 1/2 inches between any two members. When straight bars are used which are not filled in with scroll work, there shall not be more than 1 inch space between bars. When wood slats are used they shall not be less than 1 1/2 inches in width by 3/8 inch thick, with a 1 inch space between slats. Such enclosures shall be properly and securely braced and fastened.

 (a)  All installations. Shaftway entrances shall be provided with approved gates or doors, which may be of the vertical-sliding or rolling semiautomatic type or of the swinging hinged type. When shaftways are required to be of fire-resistive construction, fire doors shall be provided at all landings. Landing doors and gates shall be equipped with an effective lock or latch. The openings at shaftway entrances shall in no instance be greater than the width and height of the car. Larger openings are permitted, if they are limited to the car size by bolted transoms or side panels.

 (b)  New installations. The shaftway landing doors of power-driven dumbwaiters shall be provided with a locking device which prevents the normal operation of the car so long as any door or doors are in an opened position. Such locking device shall also lock the door or doors on the shaftway side while the car is not at the landing.

 (a)  The cars of newly installed dumbwaiters shall be of substantial construction. The horizontal cross sectional area shall not exceed 9 square feet and the compartment height shall not exceed 4 feet. The carrying capacity of dumbwaiter cars shall not exceed 500 pounds. All cars of dimensions and carrying capacities greater than those specified will be considered as freight elevators and shall comply with freight requirements in every respect. The stated dimensions and capacity also apply to existing installations, except that if local conditions necessitate modification, the Department may, upon request, grant relief according to the existing exigencies.

 (b)  New dumbwaiter cars shall be enclosed to the full height on all sides not used for loading or unloading. When considered necessary by the Department, the cars of existing dumbwaiters shall also be enclosed to the full height under beam, except on the sides used for loading and unloading.

 (a)  Power-driven dumbwaiters shall be provided with one or more iron or steel hoisting cables, equivalent tapes, or chains. If cables are exposed to corrosion, they shall be covered with marline or other equivalent protective covering.

 (b)  The loads on hoisting cables shall be determined by the factors of safety as given in the following curve, in accordance with the rated speed of the car:

 (c)  The hoisting and counterweight cables of all power-driven dumbwaiters shall not be lengthened or repaired by splicing.

 (d)  The drum ends of new hoisting and counterweight cables shall be secured by clamps placed on the inside of the drums.

 (a)  No single-belted or chain-driven dumbwaiter shall have a car speed in excess of 50 feet per minute. No new power-driven dumbwaiter shall be operated by hand rope control.

 (b)  New power-driven dumbwaiter machines of the winding drum type shall be equipped with an automatic terminal stop which automatically cuts off the source of power and applies the brake. Limit switches may be used in lieu of machine automatics.

 (c)  Dependable brakes shall be provided for all dumbwaiters.

 (d)  A slack cable device shall be provided on newly installed dumbwaiters of the winding drum type above a car travel of 30 feet and a capacity of 100 pounds. Such device shall automatically stop the machine and apply the brake in the event of broken or slack hoisting cables.

 (e)  The removal and reerection of any dumbwaiter in a new location shall be in conformity with the requirements for new installations.

 (f)  When the space below the hoistway of new installations is used for a passageway or is occupied by persons, or if unoccupied is not secured against unauthorized access, cars and counterweights shall be provided with safeties which operate on the breaking of the suspension means.

 (g)  Pushbuttons shall not be permitted to control the operation of any dumbwaiter in school buildings, sanitariums for the weak-minded, and similar classes of buildings if there is danger of abuse of the purpose of such buttons, unless the pushbuttons may be made inaccessible to the occupants or are key operated. A decision on this point will be made at the time of the approval of the plans for the dumbwaiters.