Lifter borers, used extensively in the power supply industry, can be exposed to severe loading as they install and remove power poles.
In early 2016, a lifter borer boom that was nearly 20 years old broke off close to its pivot point as the machine was attempting to pull a pole out of the ground. Due to the location of the operator’s seat, had the boom dropped, the operator could have been seriously injured or killed.
A preliminary investigation indicated the following factors contributed to the incident:
- Insufficient maintenance and inspection
- A large amount of grease and grime that may have hidden cracks
The Queensland regulator says it is critical that all lifter borers are adequately maintained and inspected in accordance with the manufacturer’s instructions.
A number of lifter borer manufacturers specify that a major strip-down inspection be carried out at least once every 10 years. This is consistent with the information provided in the Mobile Crane Code of Practice for major inspections on mobile cranes, which can be accessed from www.worksafe.qld.gov.au.
The annual crane inspection must be carried out by a competent person who can demonstrate they have adequate training, knowledge and experience to carry out the task.
While the competent person does not have to be independent, engaging an independent competent person who is not involved in maintenance of the crane is consistent with the Australian Standard, AS 2550 Cranes – Safe Use.
This safety alert can be accessed from https://www.worksafe.qld.gov.au/injury-prevention-safety/safety-alerts/whsq/2016/lifter-borer-boom-failure. Australian Standards can be purchased from here.
- Lack of equipment maintenance, leading to failure of interlocks of the grate over the hopper
- Poor hopper design, making it difficult to clean from the outside of the hopper with water
- Controls between the water and agitator being too close
- Lack of operator training, inadequate instruction and supervision
- Safe work method statements (SWMS’s) do not adequately reflect accessing the hopper for clean-out purposes
According to WorkSafe WA, the employer or person in control of the workplace must ensure all vehicle-mounted concrete boom pump operators hold a high-risk work license. Also, workers must be adequately supervised and trained in using safe operating procedures.
Employers should ensure that:
- SWMSs are conducted, and the need to enter the hopper is fully explained and understood by workers
- The hopper is fitted with a secured hopper grate, or the hopper grate is interlocked with an emergency stop button
- A risk assessment on all tasks is performed by the employer or person in control of the workplace.