Overhead power lines
Overhead power lines can be found in many places and usually, they pose little risk to people carrying out everyday work tasks. However, when those tasks involve moving objects of considerable height, the danger of coming into contact with the power line increases dramatically, together with the risk of extremely serious injuries or even death.
A recent case in which a worker suffered severe injuries following contact with an overhead power line shows how dangerous this can be, and what precautions can be taken to avoid such incidents happening.
Two construction companies have been fined after an employee suffered multiple life-changing injuries which include severe burns on his neck.
Network Rail had appointed BAM Construction to start work on a new railway operating centre in Basingstoke. BAM then appointed Shoreland Projects Ltd to be the groundworks contractor for the project.
When Shoreland began work on the installation of lampposts on the road that led to the site entrance, they were using an excavator to lift the posts into position. The fifth lamppost touched the 11kv overhead power lines, causing the employee to sustain the burn injuries.
Fortunately, a colleague was nearby and used a piece of timber to push him away from the lamppost, breaking the contact.
The HSE investigated and discovered that there had been a failure to properly identify the presence of the overhead power lines. There was no appropriate work activity plan. The companies had not put any suitable control measures in place that would have prevented contact with the overhead power lines. Because of this, a number of workers were put at risk, not only the man who sustained the injuries.
BAM Construction pleaded guilty to breaching Regulation 14 of the Electricity at Work Regulations 1989. They were fined £260,000 and ordered to pay costs of nearly nine and a half thousand pounds.
Shoreland Projects Ltd also pleaded guilty to contravening Regulation 14 of the Electricity at Work Regulations. They were fined £22,000 and ordered to pay costs of nearly eight and a half thousand pounds.
The HSE said that the case highlighted the importance for all work to be planned properly by all duty holders. Construction work carried out near live conductors needs to be properly planned, managed and monitored to ensure full control of risks.
We see this type of accident so many times.
So, what is Regulation 14 of the Electricity at Work Regulations 1989?
Work on or near live conductors
14. No person shall be engaged in any work activity on or so near any live conductor (other than one suitably covered with insulating material so as to prevent danger) that danger may arise unless– (a)it is unreasonable in all the circumstances for it to be dead; and (b)it is reasonable in all the circumstances for him to be at work on or near it while it is live; and (c)suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.
I was once asked the question “Why are overhead cables potentially more dangerous than cables on the ground?”
Very simply, overhead cables are bare conductors; they do not have any insulation unlike cables you see on the ground. This means in normal operation, they are safe. However, if a conductive material ever goes near the overhead cables, there is a very high risk of electrocution.
What can be done to prevent this occurrence?
The law requires that work may be carried out near live overhead lines only when there is no alternative and only when the risks are acceptable and can be properly controlled.
All tasks should be planned and risk assessed, but more so when working near overhead electricity cables.
The risk assessment must take into account any restrictions when it is raining or there is a damp atmosphere (this may influence safe distances).
Only trained competent workers should be employed.
Communication is vital between everyone involved in the project including the company in charge of the overhead cables.
The first question to be asked is “Can the power be locked off/diverted while work is carried out in the vicinity?”
If the answer is no, then ask “Can the work be carried out safely?” If not, then the work must not be done.
Can insulation be added to the cables?
Ensure safe distances are put in place as per HSE guidance – see link at the bottom of this article.
“Goal posts” should be erected either side of the overhead cables at crossing points to indicate safe height. Goal posts are a temporary structure with the crossbar set lower than the overhead cables. The idea is any item that can pass under the goal posts will be safe to pass under the overhead cables.
Only dedicated crossing points should be used when crossing underneath the cables.
All other access areas should be fenced off, ensuring only the dedicated crossing points can be used.
Any plant, vehicles or machinery that cannot pass safely under the goal posts must be prohibited from using the crossing points.
ALL staff (WITHOUT EXCEPTION) must be inducted before being allowed on site.
Signs should be displayed warning of the overhead danger and what to do in an emergency.
Emergency contact details should be clearly displayed
Site supervisors should monitor to ensure safe procedures are being adhered to.
The HSE provide further guidance on working safely near overhead cables: http://www.hse.gov.uk/pubns/gs6.pdf