Electrical Power Lines: Shock Horror - Safe working near overhead power lines in agriculture (HSE INDG389)

Shock Horror - Safe Working Near Overhead Power Lines in Agriculture


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This leaflet highlights the risks associated with overhead power lines in agriculture and sets out safe protocols for people who may work near these lines.


On average two people are killed and many more are injured every year when they come into contact with overhead power lines (OHPLs) during agricultural work. Contact with them rarely results in just minor injury. Machinery (such as combines, tipping trailers and irrigators), equipment (such as irrigation pipes and ladders) and activities (such as stacking) are often involved. There are also many near misses- incidents that were not reported and where no one was hurt.

If a piece of machinery or equipment gets too close to or comes into contact with an overhead cable, then electricity will be conducted through the machine or equipment to earth. It may also pass through anyone who is touching it. Electricity can arc, ie jump across gaps, so you (and your equipment or machinery) do not have to touch the lines to get a serious or fatal shock.

It is not only agricultural equipment and machinery which present a danger. A jet of water or liquid slurry, a piece of metal, a fishing rod - any of these coming into contact or near contact with an OHPL can cause a discharge of electricity and a high risk of fatal or severe shock.

Injuries are often caused by a combination of factors rather than one major event. You may be tired and less alert than usual, so you forget to check for OHPLs in the area where you are working. You may be in a hurry and take short cuts to get a job done, so you dont bring down a high-lift trailer before you move it.

One of the biggest problems is that people simply do not notice OHPLs. Lines which run across the middle of a field are clearly visible, but if you pass them every day, you stop being aware of them. Lines which run parallel to hedges or the edge of woodland and forest blend into the scenery and can be particularly difficult to spot. Some lines may run parallel to, or under, other lines and these are also hard to see.

Everyone working in agriculture should know, understand and follow safe procedures when working near OHPLs.

Line Heights

There is a minimum distance (clearance) between the power line (or cable) and the ground. The height of the cable varies according to the voltage carried - generally, the higher the voltage, the higher the power line. Figure 1 shows the types of support, voltage and clearance.

HSE_powerlinesht.jpg (30171 bytes)

Figure 1: Line heights

Assessing the risks

When assessing the risks from OHPLs, consider these four key questions:

  • What are the risks?
  • Who could be affected by them?
  • Do the existing control measures remove or significantly reduce the risks?
  • Can anything further be done?

Once you have completed your risk assessment it is important to plan any changes so they are implemented effectively.

How can I reduce the risks

Good management will reduce the risk of accidents happening. By planning carefully and putting controls in place, workers, contractors or visitors to the farm should not come into contact with OHPLs.

So what controls can be put in place? The following guidelines will help:

Think ahead

  • Use machinery and equipment safely.
  • Know the safe operating distances.
  • Plan your work so it avoids high-risk areas.
  • Use alternative access points and routes which avoid OHPLs.

Keep an eye on children and visitors on your land - a kite or a fishing rod used close to or beneath a line could set up a lethal circuit.

Map OHPL routes

  • Know your area.
  • Find out the routes and operating voltages of OHPLs running across your land or near the boundaries. The local electricity company will supply this information on request.
  • Mark routes and voltages on the farm map.

Measure your machinery

  • Find out the maximum height and vertical reach of all your machinery and equipment and that used by contractors.
  • Consider the risks associated with OHPLs when buying new or used equipment.

Inform people

  • Make sure everyone knows what they are doing.
  • Train all staff to be aware of the risks associated with OHPLs.
  • Show them the Shock Horror video (see Further reading section for details) and make sure they know what to do if there is an accident.?
  • Make sure contractors are aware of the location of OHPLs before they come onto your land. Give them the clearances. Is their machinery and equipment safe to use near lines?
  • Put up signs for anyone else who may be in the vicinity, eg fishermen, walkers, campers etc.

Consult your electricity company

  • Talk to the local electricity company. They will provide free information and advice with supporting literature about the precautions and safe working practices to be followed near OHPLs.
  • Ask them to help you plan access routes which avoid lines and tell you what to do if it is necessary to work close to the lines.
  • Consult your electricity company if you need to check your line clearances.

Re-route OHPLs

  • You may want to consider re-routing or burying the OHPLs in certain locations. Consult your electricity company. DO NOT attempt to do this yourself.
  • Creating alternative access routes and points may be a more costeffective solution.

Limit access

  • If you have to work near OHPLs, use barriers and goalposts to limit access.
  • Ensure only machines of a certain height can pass under the barriers.
  • Check the poles carrying the OHPLs and report any abnormalities to the electricity company. They should be fitted with climbing guards. If they are not, contact the electricity company for advice.
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