Avoiding Overhead Cable Strikes - HSE GS6 Goal Posts

NINJA GUARD GS6 Telescopic Goal Post

Understanding the Core Principle

The fundamental rule from HSE GS6 is to always assume that overhead power lines are live, unless and until you have formally confirmed otherwise with the line owner (e.g., National Grid, local electricity distributor). A strike can cause catastrophic electrocution, severe burns, and massive fires. The electricity can arc or "flash over" gaps, so you don't even need to touch the line to be killed.

The Hierarchy of Control: A Step-by-Step Strategy

Follow these steps in order of priority. You should always aim for the highest possible level of control.

1. ELIMINATION (The Safest Option)

Completely avoid working near overhead lines.

· Re-route the work: Can the task be done in a different location, away from the lines?

· Re-design the work: Can the project be modified so that machinery or materials never need to enter the danger zone?

· Schedule the work: Can work be planned for when the lines are not live (e.g., during a planned shutdown organised with the utility company)?

2. SUBSTITUTION

Use alternative methods or equipment that reduce the risk.

· Use non-conductive materials: Where possible, use materials that cannot conduct electricity (e.g., fibreglass goal posts instead of metal).

· Use smaller equipment: Choose machinery with a lower operating height that cannot reach the danger zone.

3. ENGINEERING CONTROLS

Implement physical barriers to prevent contact.

· Goalpost Barriers: Erect substantial "goalpost" or barrier systems that define a safe clearance distance. These must be high enough and strong enough to prevent any machinery from passing under them.

· Height Restrictions: Install physical stops on machinery cabs or booms to prevent them from being raised beyond a safe angle or height.

· Proximity Warning Devices: Fit devices that emit an audible/visual alarm when the machinery approaches a set distance from a line. Crucially, these are an aid to safety, not a substitute for planning and barriers.

4. ADMINISTRATIVE CONTROLS

Implement safe systems of work through planning and procedures.

This is where most of the day-to-day management occurs. Key actions include:

· Appoint a Competent Supervisor: Designate a person responsible for managing the safety of work near lines.

· Carry out a Site-Specific Risk Assessment: Identify all overhead lines, note their voltage (which determines the safe distance), and plan all work activities around them.

· Create a Safe Working Plan: This must be understood by everyone on site. It should include:

· Safe Clearance Distances: Mark these clearly on the ground with tape, barriers, or flags. Refer to the table below for minimum distances.

· One-Way Systems: For sites with vehicle movement, design routes that keep them well away from lines.

· Appointed Banksmen / Signallers: Use a trained signaller to guide vehicle movement, especially for large machinery like cranes or tipper trucks. The signaller must only focus on this task.

· Written Instructions: Ensure all operators and workers have clear, written instructions on the dangers and the safe system of work.

HSE GS6 Recommended Minimum Safe Clearance Distances

Voltage of Line Minimum Safe Approach Distance (From any part of the machine or load)

Up to 33 kV 6 metres

132 kV 7 metres

275 kV 8 metres

400 kV 9 metres

If you cannot identify the voltage, assume it is the highest and use 9 metres.

5. PERSONAL PROTECTIVE EQUIPMENT (PPE)

PPE is the last line of defence and is ineffective against the immense power of an overhead strike.

· PPE will not protect you from electrocution if you contact or come too close to a high-voltage line.

· Flame-retardant (FR) clothing may offer some protection against arc flash, but it will not prevent electrocution.

Key Responsibilities for Different Roles

· For Site Managers / Planners:

· Contact the line owner early to get information on voltages and discuss options like temporary isolation or earthing of the lines.

· Ensure the Safe System of Work is in place, understood, and followed.

· Provide adequate signage and barriers.

· For Machinery Operators (Cranes, Tipper Trucks, Excavators, etc.):

· LOOK UP AND LIVE. Make it a habit to do a 360-degree scan for overhead lines before you even get in the cab.

· Know the maximum height of your vehicle and its load.

· Never operate machinery alone near overhead lines.

· Obey all barriers and instructions from the banksman.

· If you are in any doubt, STOP and seek clarification.

· For Ground Workers:

· Be aware of the dangers, especially when moving long objects (e.g., ladders, pipes, scaffolding).

· Never store materials or park vehicles under or near overhead lines.

What to Do in an Emergency (If a Strike Occurs)

1. STAY IN THE CAB. If you are in a vehicle that contacts a line, the safest place is inside. The electricity will flow through the metal frame into the ground.

2. WARN OTHERS. Shout to everyone else to STAY AWAY. Anyone who touches the vehicle will be electrocuted.

3. JUMP CLEAR (Only if you MUST exit). If there is a fire and you must get out, jump out as far as you can with your feet together. Do not allow any part of your body to touch the vehicle and the ground at the same time.

4. SHUFFLE AWAY. Once on the ground, keep your feet together and shuffle away. This prevents "step potential" where voltage can travel through the ground and up one leg and down the other.

5. CALL 999. Inform the emergency services that it is an electrical incident.

6. CALL THE NETWORK OPERATOR. Contact the electricity company to isolate the power. Keep their number on site.

In summary: Plan, avoid, barrier, and supervise. Always look up and assume every line is live.

For the definitive guide, always refer to the latest version of HSE GS6 directly https://www.hse.gov.uk/pubns/gs6.pdf