Operating near powerlines
Setting-up near powerlines or electrical equipment
Working near powerlines is restricted under:
- the !variable [css/ssi/links/electrical_safety.inc] not found! which regulates work around overhead power lines.
- practical advice is provided in the Code of Practice - Working Near Exposed Live Parts.
One of the requirements is that workers and plant should maintain an 'exclusion zone' of 3 metres around live overhead power lines of up to 132kV.
Greater 'exclusion zones' apply to high voltage lines (6 and 8 metres depending on the voltage).
In certain limited situations, exceptions may apply - refer to Appendix B of the Code of Practice - Working Near Exposed Live Parts for further details.
When operating plant near power lines, you must have an 'exclusion zone' around overhead power lines:
- The minimum clearance distance from the closest part of the concrete placement boom to the power line is the 'exclusion zone'.
- Allowing for sway and sag of the overhead lines. Sway is usually caused by wind and sag occurs when the temperature of the line fluctuates.
- Making sure that persons, plant and vehicles stay outside the 'exclusion zone' at all times.
- Nominating a 'safety observer' when the crane or plant could enter into the 'exclusion zone'.
There are a number of devices available to prevent contact with power lines, or reduce the degree of risk in the event of contact including:
- The use of 'tiger tails' on power lines act as a visual aid to prevent contact by highlighting the location of the power line. Note: tiger tails do not insulate the wires and therefore the 'exclusion zone' must be maintained.
- Limiting or warning devices to prevent the pump boom from entering the exclusion zone and the system should be designed to 'fail safe' or should at least meet category 4 reliability in accordance with AS 4024.1 Safeguarding of machinery - General principles (non-Queensland Government link) or EN 954 -1 European Norm ¿ Safety Related Parts of Control Systems.
- Earthing of concrete placing booms should be in accordance with the Code of Practice - Working Near Exposed Live Parts.
Irrespective of whether safety devices are being used, the 'exclusion zone' must not to be encroached.