Overhead power lines
- Introduction
- Managing the risk
- Removing or reducing the risk
- Safe use of machinery and vehicles
- Training
- Emergency action
- Case study - OHPL
Introduction
Many farms have overhead power lines (OHPLs) running across them. These lines are a hazard to workers in agriculture. Coming into contact with, or even coming close to these lines (electricity can flash over), while using farm machinery, such as tipping trailers or boom sprayers, or during activities, such as stacking, can lead to the death of workers.
Managing the risk
To reduce the risk to workers’ safety, find out:
- where the overhead lines are;
- what their operating voltage is;
- what the maximum working height is under these lines;
- the maximum height and vertical reach of the machinery in use on the farm (including that used by contractors where relevant).
Mark these details on the farm map so that it can be used as a reference when planning work, instructing contractors or operators, or buying new equipment.
Contractors are at risk when they work on farms where overhead lines are present. Make sure they know where the lines are, and tell them the precautions they need to take. Routes can be marked with safety signs to warn all visitors of the dangers.
When assessing the risks from OHPLs, talking to your employees about how they do their work can be very valuable. Use trade union or other employee safety representatives to help you.
Removing or reducing the risk
There are a number of steps that can be taken to remove or reduce the risk:
- Diverting lines, either by burying lines or changing routes. This may be particularly suitable for lines that go over, or close to farmyards. Consult with the body responsible for the line.
- Purchasing machinery that do not have vertical reach or a maximum height that may create the risk of contact or flash-over.
- Creating alternative access points and routes to avoid OHPLs.
- Erecting “goal posts” or barriers so that machines that have to pass beneath lines can be limited to a safe height. This is particularly effective for traffic routes and gateways.
Safe use of machinery and vehicles
Among the operations that may put workers at risk from OHPLs are:
- stacking bales or potato boxes;
- folding sprayer booms;
- tipping trailers or lorries;
- operating materials handlers;
- working on top of combines or other high machinery.
Risks can be reduced by:
- using sprayers with horizontally folding booms;
- never folding sprayer booms on the move;
- taking care not to damage poles and stays;
- making sure machinery can operate safely near any overhead lines;
- fitting shorter radio aerials or repositioning existing ones on high machines so they cannot cause danger;
- carrying irrigation pipes horizontally using two people and not storing pipes or other materials and equipment near or under power lines and their supports;
- designating safe areas for high-risk operations, e.g. boom folding, telescopic handler use, tipping trailers.
Training
Everybody who works near overhead power lines with a machine or equipment needs to know what the dangers of overhead lines are, the precautions to follow and what to do if they do contact a power line.
Emergency action
- Never touch an overhead line - even if it has been brought down by machinery, or has fallen. Never assume lines are dead.
- When a machine is in contact with an overhead line, electrocution is possible if anyone touches both the machine and the ground. Stay in the machine and lower any raised parts in contact or drive the machine out of the lines if you can.
- If you need to get out to summon help or because of fire, jump out as far as you can without touching any wires or the machine - keep upright and away.
- Get the electricity company to disconnect the supply. Even if the line appears dead, do not touch it - automatic switching may reconnect the power.
Case study - OHPLs
A tractor driver was electrocuted after his tipping trailer touched an 11 kV overhead power line. He had been carting manure to a heap which was near the power line. He tipped the trailer and pulled forward to empty the load. The 6.75 m trailer touched the 6.5 m high power line. He was electrocuted when he got out of the tractor.
Keep clamps, manure heaps and bale stacks away from power lines.
