WHSQ safety alert highlights risk of hoist rope failure and loads dropping from mobile and tower cranes

Workplace Health and Safety Queensland's safety alert highlights risk of hoist rope failure and loads dropping from mobile and tower cranes, warning that operators of lifting equipment across construction and industrial sites need to take note. The regulator says this can happen when the hoist limit is disabled or does not function correctly on plant used for lifting operations.

Four incidents where hook blocks have fallen due to the hoist limit not functioning correctly have been reported in the last three years, according to WHSQ. These failures point to a broader risk of hoist rope breakdown affecting mobile plant and tower cranes alike, and they serve as a reminder that even well-established lifting systems can fail without proper checks.

What Caused the Hoist Rope Failures?

According to WHSQ, the hoist rope broke in three tower crane incidents, dropping a heavy hook block from the crane boom. In the 2019 incident involving a hammerhead tower crane rigged with two falls of rope, the hook block and a load of scaffold stair modules fell approximately 40 metres and hit the ground close to a pedestrian and a worker nearby.

"Any hoist limit system set up on a mobile, or tower crane should ensure two blocking cannot occur, irrespective of the hoist speed, the number of rope falls or the boom luff angle," WHSQ stated in the alert.

How to Prevent Hoist Limit Failures on Cranes

To prevent two blocking, crane operators must ensure all safety features provided by the crane manufacturer, including the hoist limit, remain operational and are not to be overridden for normal operation of the plant. Additionally, hoist limits should be set up in accordance with the manufacturer's instructions for each specific piece of equipment.

Key actions for businesses operating mobile or tower crane equipment include:

• Verifying hoist limit systems function correctly before every lifting task
• Never overriding or disabling safety features built into crane equipment
• Following manufacturer instructions when setting up hoist limits on any equipment
• Training workers to recognise signs of hoist rope wear or system malfunction
• Reviewing crane equipment regularly as part of broader health and safety risk management strategies

WHSQ urges employers, builders, workers, and crane operators to apply the principles in this alert to any mobile or tower crane equipment fitted with a hoist rope. Businesses managing multiple pieces of lifting plant should treat this safety alert as an opportunity to review existing procedures, particularly where mobile cranes have previously been targeted in safety blitzes for similar compliance issues.

A robust occupational health and safety management system should include clear protocols for equipment checks, ensuring hoist limits and other safety features are tested before plant is put into service. Businesses can also strengthen their documentation with a Work Health and Safety Manual tailored to crane and lifting operations.

For more information on the above safety alert, go to the WHSQ website.