Current through Register Vol. 46, No. 45, November 2, 2024
Section 23-8.3 - Special provisions for tower cranes(a) Tower crane erection. (1) Every tower crane used in construction shall be erected in accordance with the manufacturer's recommendations and under the supervision of a competent, designated person experienced in tower crane erection.(2) Prior to the erection of any tower crane the ability of the supporting system, including slabs, foundations and the underlying soil to support the loads intended to be imposed thereon shall be certified by a professional engineer licensed to practice in the State of New York.(3) Tower cranes shall be erected so that the jibs and counterweights can swing 360 degrees without striking any building, structure or any other object.(4) Prior to initial use, a newly erected tower crane shall undergo a static overload test in the direction of least stability. Such test shall consist of suspending a load at the rated load and at the maximum radius for a period of at least one hour. Subsequent to such test, settlement of the equipment and load-bearing foundation shall be within the limits specified by the tower crane manufacturer. A written report of such test shall be kept on the job site available for examination by the commissioner.(b) Tower crane capacity chart. Every tower crane shall be provided with a capacity chart which shall be posted and maintained legible in the cab of the crane clearly visible to the operator from his operating position. Where a remote control stand is used a duplicate of such capacity chart shall be affixed to such control stand. Such capacity chart shall be furnished by the manufacturer of the crane and shall include a full and complete range of crane load ratings at all stated operating radii for each allowable speed and for each recommended counterweight loading.(c) Tower crane construction. (1) Limit switches. Limit switches which shall be sealed against unauthorized tampering shall be provided as follows: (i) To limit trolley travel at either end of the jib.(ii) To limit load block upward motion to prevent two-blocking.(iii) To limit the load being lifted to no more than 110 percent of the rated load upon completion of the static overload test as specified in paragraph (a) (4) of this section 23-8.3, above.(2) Cabs and remote control stations. (i) Tower crane cabs and remote control stations for such cranes shall be protected from falling objects and material and from the elements.(ii) Cab windows shall be constructed of transparent safety glazing material and shall provide clear visibility in all directions.(iii) Cabs and remote control stations for tower cranes shall be heated to a temperature of at least 60 degrees Fahrenheit during cold weather whenever occupied.(iv) Cabs and remote control stations for tower cranes shall be adequately ventilated.(3) Accessibility. Adequate and safe means of access to and egress from the cabs and machinery platforms of tower cranes shall be provided. Where it is necessary to inspect the jib attachments located on the jib of any tower crane, a footwalk with suitable handrails shall be provided for such inspections.(4) Brakes. In addition to the hoisting brakes required by this Subpart, tower cranes shall be provided with the following: (i) Slewing brake. Every tower crane shall be provided with a brake having adequate holding power in either direction to prevent movement of the jib when desired during normal crane operation. Such brake shall be capable of being set in the holding position and kept there without attention from the operator.(ii) Trolley brake. The trolley of every tower crane shall be provided with an automatic brake or device capable of stopping movement of the trolley in case of trolley rope breakage.(5) Electrical equipment. (i) All electrical equipment of tower cranes shall be grounded.(ii) All tower cranes shall be provided with lightning protection.(iii) All controls of tower cranes shall be of the deadman type.(iv) In the event of power failure, all tower crane brakes shall be set automatically.(6) Climbing jacks. Where climbing jacks are provided for tower cranes such jacks shall be equipped with over-pressure relief valves, pressure gages and check valves designed to retain pressure in case of hydraulic line failure.(7) Wind velocity device. Every tower crane shall be provided with a device for measuring wind velocity. The sensing portion of every such device shall be mounted on the highest point of the crane while the readout of every such device shall be located in the cab or remote control station of the tower crane.(8) Counterweights. Counterweights used on tower cranes shall be in accordance with the manufacturers' recommendations. Counterweights shall be securely fastened to the counter jib to prevent pieces from being accidentally dislodged.(d) Inspection and maintenance. (1) Tower cranes shall be inspected and maintained in accordance with the manufacturers' recommendations.(2) Where the mast of any tower crane runs through floor openings in the building or other structure in which the crane is mounted and the mast is secured by wedges or braces, such wedges or braces shall be inspected for tightness and dislocation at least twice each working day.(e) Operation of tower cranes. (1) Operators. Tower cranes shall be operated only by persons who are qualified in accordance with the provisions of section 23-8.5 of this Subpart.(2) Operation in windy conditions. Tower cranes shall not be operated when the wind speed is at any time greater than 30 miles per hour. Tower cranes shall not be raised to new operating levels when the wind speed exceeds 20 miles per hour.(3) Operation without counterweight prohibited. No tower crane shall be operated without the full amount of ballast or counterweight in place as specified by the manufacturer or builder of the crane or by a professional engineer licensed to practice in the State of New York.N.Y. Comp. Codes R. & Regs. Tit. 12 §§ 23-8.3