20090201 - 166 - Bsu Safety Alert - Operating Under Power Lines Fatality

SAFETY ALERT #166 Dated: Sunday, 1st FEBRUARY 2009 Title:

OPERATING UNDER POWERLINES FATALITY

In the course of a highways project, concrete was being poured on the final layer of a box culvert wall. The person operating the remote control that moves the boom of the concrete pump failed to take account that he was operating directly underneath 33kV overhead power lines. That person was only a few metres from the hose at the time. He elevated the boom high enough for it to come into direct contact with the power line. Burn marks on the boom showed clearly where it had made physical contact. As a direct result the man supporting the hose was electrocuted. The failings are wide and varied. There appears not to have been a safe system of work in place for this highly hazardous activity. No measures seem to have been taken to highlight the presence of the power lines and their proximity to the works. The fact that so many people were in the area at the time that would have seen the power lines and did not address the hazard indicates an entirely negative safety culture. Only by the contractor playing his part in raising awareness can this scenario not be repeated. There is a need to raise awareness at all levels in the organisation and to ensure that all persons are trained in the health and safety measures needed in respect of each task. Specific controls are required in respect of operations such as this and are listed as follows: • • • • • • •

Establish maximum height and vertical reach of all plant and machinery. Mark routes of all overhead power lines prior to commencing work. Ensure that the maximum working height for working under each span of overhead line is made known to all operatives. (The minimum clearance for plant and equipment operating under voltages of up to and including 33kV is 5.2 metres.) If the work is to be undertaken over a long period of time it may be advisable to consult with the service provider and arrange for overhead power lines to be diverted for the duration of the works. Erect goalposts and barriers to ensure that plant and equipment are restricted to a safe height. Ensure that all personnel working near overhead power lines are fully briefed on the dangers associated with the activity, the precautions to be followed and actions to be taken in the event of an emergency. They must also be told that arcing can occur and that direct contact with the power lines might not necessarily be a cause of accidents happening. Assume that all overhead power lines are live

Following the investigation, the root causes found were as follows: • • • •

A failure to plan the work and identify the risks associated with working under live overhead power lines. An absence of supervision by a competent person during the course of the work. A failure to put goalposts in place to restrict the height to which the boom could be raised. A collective failure on the part all persons in the vicinity at the time of the accident to recognise a dangerous situation arising.

The following remedial measures have been recommended aimed at preventing a recurrence: • • • •

A full and suitable risk assessment of operations under live overhead power lines is to be carried out. These operations are to be closely supervised by a competent person. All personnel are to be fully briefed on the dangers of working underneath live power lines, the precautions that must be followed and what to do in the event of an accident or emergency. Minimum clearances in respect of each voltage must be established and goalposts and barriers put in place as appropriate.