Overhead Line on the Access Track
Your telehandler is parked at the site compound. The only route to the rear of the building is a tracked haul road that passes under an 11 kV overhead line. The line runs roughly parallel to the road for 40 m and crosses it once at a point where the conductors are about 5.8 m above ground at the lowest sag. Your machine is 2.9 m to the top of the cab, and you will be carrying a 3.2 m long bundle of scaffold tube on the forks with the boom lowered to travel position, giving a total height of about 3.4 m. The site has no goalposts or height restriction barriers on that crossing. A banksman is available but is currently directing a dumper on the other side of the site. The line operator's safety distance for plant is 9 m for lines up to 33 kV unless switched out and proved dead.
1. Explain whether the planned route is acceptable and what controls are needed before you travel it.
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The route is not acceptable as described. Your travel height of about 3.4 m is under the 5.8 m conductor sag, so a simple vertical clearance check passes - but that is the wrong check. The required control is the 9 m safety distance from the line, measured in three dimensions, and the machine will pass directly beneath the crossing. Passing under a live 11 kV line at any distance less than the safety distance is prohibited unless the line is switched out and proved dead, or the line operator has agreed a deviation in writing with engineered controls.
Controls needed before travel:
- Isolate and prove dead the line, with a permit and confirmation from the line operator, or
- Agree a formal deviation with the line operator, install goalposts and height restriction barriers at the crossing, and mark the safe route.
- Brief all operators on the crossing, the barriers and the no-go zone.
- Provide a banksman at the crossing for every movement.
Until one of those is in place, do not travel the route. Find an alternative or wait.
2. The banksman is tied up elsewhere. What is the risk of travelling without them, and how do you handle the delay?
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Travelling under a live line without a banksman removes the second pair of eyes at the exact point of highest consequence. The operator's attention is on the load, the road surface and the machine; the banksman's job is to watch the line, the load height and the crossing point. Without them, a small boom movement, a load shift or a misjudged turn can bring the machine or load inside the safety distance with no warning.
The delay is not a reason to proceed alone. You should stop, report to the supervisor that the crossing cannot be used without the agreed controls, and either wait for the banksman or use an alternative route. Record the stoppage and the reason. If the supervisor directs you to cross without controls, refuse and escalate - an instruction to breach a safety distance from a live 11 kV line is not a lawful instruction to follow.