Operating Cranes and Plant near Overhead Electric Lines
Workplace Health and Safety Queensland has issued an alert aimed to assist employers and operators of the dangers associated with operating plant and cranes near overhead powerlines.
This post by SafetyCulture.com describes the alert in detail:
Workplace Health and Safety Queensland has issued an alert regarding contact with overhead electric lines when operating a crane or other plant.
It is a risky scenario as as it can be extremely difficult for crane or plant operators to see or judge distances from them.
Actual contact with the lines is not needed to deliver an electric shock, as a close approach to the line conductors may cause a ‘flashover’ or arc.
Before operating a crane or item of mobile plant, a worksite inspection should be conducted to identify potential hazards such as overhead electric lines or other electrical equipment. A risk assessment should include:
the location and voltage of the overhead electric lines
the nature, size and shape of the load to be moved
the setting up and packing up processes
the type of crane, mobile plant, machinery and equipment used and its design envelope
the stability of crane or mobile plant and suspended loads
site conditions, including unexpected movement of the terrain, ground or surface upon which the crane or plant is located
the prevailing and unexpected wind strength and direction and weather conditions
the qualifications, competency, skill and experience of people doing the work
traffic or pedestrians that could interfere with the work
the minimum clearance distance from the closest part of the crane or other operating plant to the electric line
whether the load is being carried above the electric lines and may accidentally fall onto the energised lines
the possibility of sway and sag of the overhead electric lines
the possibility of the crane or plant becoming energised through voltage induced by adjacent electric lines, especially high voltage lines
how the load being carried by a crane is secured and whether any part of the load may inadvertently move during the operation and encroach on the authorised person zone
the potential for inadvertent movement of the crane or mobile plant, the load, people and electrical equipment in the area
the functional behaviour of the crane, load or plant that could result in inadvertent contact with overhead electric lines.
Electric lines should always be treated as energised unless the operator of the crane or mobile plant has received an access authority or other form of written documentation from the electricity supply authority which allows people to work within the no-go zone.
Contact with overhead powerlines can pose a serious risk of electrocution when operating a crane or other plant because of the difficulty they experience judging the distance between the crane and the powerlines overhead.
Workers on a construction site, whether working with plant and machinery or not will encounter this equipment at some time or the other due to their prevalence on site. It is difficult to imagine a construction without plant or machinery, especially commercial sites. Therefore it is important for uncertified persons who have not been trained in crane operation to be aware of safety procedures for plant and machinery. These plant and machinery include cranes, concrete booms, elevating work platforms, earthmoving equipment etc.
In order to manage the risk involved with operation of plant and machinery, first these risks need to be identified. An inspection to identify the risk involved with setting up cranes or other equipment in the vicinity of power lines should be carried out. The crane or machinery operator should be included in the risk identification process together with the employer.
When working with power lines overhead, authorities suggest you treat all electric power lines as live and either have them de-energised or create an exclusion zone around them and keep workers out. De-energising power lines should only be done once arrangements have been made with electricity authorities during the planning stages.
Once the risks have been identified, the employer should conduct a written assessment of the risk and it’s potential for harm.
By following the appropriate measures, employers and operators can reduce the number of operator injuries and deaths that occur each year as a result of contact with overhead powerlines.
Posted by Steven Asnicar