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Subchapter 6. Elevator Safety Orders
Article 12.3. Special Purpose Personnel Elevators

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§3085.20. Driving Machines and Sheaves [Rule 1502.10].

(a) Driving machines shall be of the traction, drum, screw, or rack and pinion type. The installation of belt-drive and chain-drive machines is prohibited. [1502.10a]

(1) Screw machines shall conform to the requirements of Section 3088.

(2) The rack and pinion drive shall consist of one or more power-driven rotating pinions mounted on the car and arranged to travel on a stationary vertical rack mounted in the hoistway. The drive shall have at least one pinion, one rack, and two backup rollers. The pinion and rack shall be of steel with a minimum safety factor of eight for the pinion and the rack. Driving machines located within the car shall be fully enclosed with solid or openwork metal which shall reject a ball 1/2 in. (13 mm) in diameter and which shall be locked.

(b) Winding drums, traction sheaves and overhead and deflecting sheaves shall be of cast iron or steel and of a pitch diameter or not less than 30 times the diameter of the wire suspension ropes. The rope grooves shall be machined. [1502.10b]

EXCEPTION to subsection 3085.20(b): Where 8 x 19 steel ropes are used on a drum type machine installation, the pitch diameter of drums and sheaves may be reduced to 21 times the diameter of the rope.

(c) The factor of safety for driving machines and sheaves shall conform to the requirements of subsection 3038(c). [1502.10c]

(d) Bolts transmitting torque and set screws shall conform to the requirements of subsection 3038(d). [1502.10d]

(e) Friction-gearing or clutch mechanisms shall not be used for connecting the drum or sheaves to the main driving mechanism. [1502.10e]

(f) Worms and worm gears made of cast iron shall not be used. [1502.10f]

(g) Driving machines shall be equipped with brakes meeting the requirements of subsection 3038(h). [1502.10g]

(h) A single ground or short circuit, a counter-voltage or a motor field discharge shall not prevent the brake magnet from allowing the brake to set when the operating device is placed in the stop position. [1502.10h]

(i) A permanent, safe and convenient means of access to elevator machine rooms and overhead machinery spaces shall be provided for authorized personnel. [1502.10i]

(Title 24, Part 7, Section 7-3085.20)

NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.

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