ESW - 28 : Safety Practices for Special Overhaul / Repair Works on Elevator (Lifts) / Escalators

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Safety Practices for Special Overhaul / Repair Works on Lifts / Escalators

Some overhaul/repair works in the industry such as the replacement of main hoisting ropes in traction drive lift, the replacement of hydraulic jack in hydraulic lift, the replacement of safety gear etc. require special attention on the employees’ safety and health at work. 

A proprietor/contractor should devise a safe system of work for a special overhaul/repair work by taking into consideration the current legal safety requirements and the instructions, in particular, the safety precautions and warnings included in the maintenance manuals published by the lift/ escalator manufacturers. 

All the engineers/supervisors and workers should observe and follow strictly the safe system of work and the safety instructions of the maintenance manuals. Any alteration and deviation to the safe system of work and/or the safety instructions in the maintenance manual should be made only under the instructions and supervision of persons who are competent and having the appropriate technical skill and experience. 

In addition to the relevant safety precautions as mentioned in the previous section, special attentions should be paid to the following when carrying out the special overhaul/ repair works:

1. During the special overhaul/repair works, safe method of lifting or mechanical handling of spare parts such as the lift car or hydraulic jack, etc. should be devised in advance in the site safety assessment. Reference should be made to the recommended method of the maintenance manual published by the manufacturers.
2. The wire rope used for rigging a lift car should be of adequate strength and length. The sharp corners of the lift car should be padded to avoid any damage to the wire rope.
3. During the lifting of a lift car, the wire rope should be fixed at the anchorage points for the frame instead of tying around the top beam of the lift car. The wire rope should preferably be of simple 1:1 suspension system at the anchorage points in order to eliminate the relative movement of wire rope with respect to the anchorages.
4. If the wire rope is tied around a diverter pulley for lifting a lift car with a 2:1 suspension system, the wire rope should be placed in the groove of the pulley.
5. Lifting hook spreaded beyond the allowable limit should be discarded immediately.
6. When a wire rope is required to be looped or is making short bend, thimbles should be used in the application. U-bolts of all clamp fastening should be on the dead end of the wire rope.
7. In clamping a wire rope into an eye, the loose end should be clamped against the main rope with minimum three clamps. The distance between two clamps should be 6 to 7 times the rope diameter apart. Clamp fastenings should be inspected and maintained regularly.
8. As a safety precaution, when the lift car (with its car top as the working platform) is hoisted up to the required position for working purposes, the safety gear of the lift car should be immediately activated so as to securely fix the lift car in position.
9.  Main Hoisting Rope Replacement Work
1. Replacement of all the old main hoisting ropes in one goal for a traction drive lift is not recommended. For the sake of safety during the rope replacement work, at least some numbers of the old hoisting ropes should remain intact to hold the lift car in case of emergency.
2. The main switch of the lift should be turned off, locked out and tagged. Proper warning notices warning that the lift is out of service should also be posted at prominent positions so as to avoid any disturbances caused by the persons in the building intending to use the lift.
3. The counterweight should be set at the lowest level at the lift pit and should be securely and adequately supported to prevent it from moving during the replacement work.
4. For easy and safe handling of new hoisting ropes during the rope replacement work, the new ropes to be used should first be cut to the required length before delivering to the work site.
5. For safety sake, the old hoisting ropes should be replaced with the new hoisting ropes one after the other.
6. In replacement of the main hoisting ropes, the old ropes should be properly transported down to the ground for removal from the work site. Safety requirements for Manual Handling and Mechanical Lifting in sections 7.2 and 7.3 of this Code should be complied with.
10. Hydraulic Jack Replacement Work
• The main switch to the hydraulic lift should be turned off, locked out and tagged.
• The pressure at the hydraulic jack to be replaced should be released and the jack should retract completely to the lowest position after the hydraulic lift car has been supported by the lifting appliance installed at the top of the lift well or at the machine room located above.
11. Safety Gear Replacement Work
• The lift car should be set near the bottom terminal landing to reduce the risk of falling from height during the replacement of safety gear at the bottom of the lift car.
• Proper working platform erected from the lift pit should be provided for the working personnel carrying out the safety gear replacement work.
12. After the special overhaul/repair work, the lifting appliance and the lifting gear for lifting/rigging purposes should be dismantled properly and the support for counterweight should also be removed before putting back the lift to normal service in the building.