Cable jointing connects sections of electrical cable to form continuous circuits in power distribution networks. Both high voltage and low voltage jointing involve working with potentially live cables, using heat shrink materials and resins, and operating in excavations or confined spaces. Incorrect jointing causes cable failures, fires, and electrocution. This talk covers the controls for safe cable jointing on site.
Key Hazards
Electrocution from incorrectly identified or inadequately isolated cables
Burns from heat shrink torches and hot resin compounds during joint assembly
Toxic fume inhalation from heated jointing compounds in enclosed excavations
Cable joint failure under load causing fire or explosion after energisation
Control Measures
Confirm cable identification and isolation with the asset owner before cutting or jointing any cable.
Prove dead at the point of work using an approved voltage indicator tested before and after use.
Apply personal safety earthing straps to both cable ends before commencing any jointing work.
Use the manufacturer's specified jointing kit and follow the instruction procedure exactly.
Ensure adequate ventilation when using heat shrink torches or resin compounds in enclosed excavations.
Wear insulated gloves rated for the cable voltage during all phases of the jointing operation.
Keep the jointing area clean and dry throughout the assembly to prevent contamination of the joint.
Record all joint details including cable reference, jointer identity, and materials used in the log.
Carry out insulation resistance and continuity tests before any joint is approved for energisation.
Emergency / Rescue
If a cable flashes or arcs during jointing, move away immediately and do not touch either cable end. Call the asset owner's emergency number and 999. Evacuate the excavation and keep everyone at least 15 metres from the fault.
Remember
Confirm cable identification and isolation with the asset owner before cutting or jointing
Prove dead with an approved voltage indicator tested before and after at the point of work
Apply personal safety earthing straps to both cable ends before starting any jointing work
Follow the manufacturer's jointing procedure exactly using the specified kit and materials
Record all joint details including cable reference, jointer identity, and materials in the log
Applicable Legislation: Electricity at Work Regulations 1989 · HSE GS38 (Electrical Test Equipment) · Health and Safety at Work etc. Act 1974 · CDM Regulations 2015