Industry warned of safety risks for mast climbers

The construction industry has been warned to check for mechanical faults in mast climbers used on high rise sites across the UK.

The Health & Safety Executive (HSE) has published an alert on aerial work platforms (MCWP), commonly known as mast climbers, which are used to support work at height.

Mast climbers use a motorized drive unit to raise and lower thin vertical masts and are often used as an alternative to large-scale scaffolding. They can be used as lifts as well as elevated work platforms and are frequently used in paving operations.

The regulator explained that mast climbers who use two independent motor drive units per mast are often not equipped with the appropriate controls to manage the risk of falling from height at excessive speed.

“Platforms can fall from heights when mechanical faults in drive units go undetected. If not corrected quickly, the fault could lead to serious injury or even death,” the HSE warned.

He explained that a drive unit malfunction could occur when the centrifugal brakes or automatic brakes did not work properly. Centrifugal brakes are meant to limit the descent speed and automatic brakes are meant to kick in whenever the platform comes to a stop.

The HSE has called on industry to urgently establish checks to detect mechanical failures in the various safety systems.

The safety body also warned that drive units can be damaged if power is applied at the end of the lift’s stroke. Care must also be taken that the platforms are not overloaded. Inspections and tests should be planned and carried out regularly by competent inspectors. Operators must also be skilled and trained in the correct emergency platform lowering procedures to prevent overheating of the drive motor.

The HSE also drew attention to the correct placement of limit switches and audio visual alarms, and the need for visual checks before use.

In May 2021 father and son David and Clayton Bottomley died while working from a mast climber on a construction site in Liverpool. The platform collapsed from a height of over 100 feet.

Falls from heights have long been the leading cause of fatal injuries on construction sites, accounting for 41% of fatalities among construction workers between April and December 2021.

This week, safety improvement notices were served on Laing O’Rourke and Bouygues after a worker was injured after falling from a height of 5 meters at the site of the Hinkley Point C nuclear power station .

Alice F. Ponder