Lightning Protection System Maintenance Checklist

A lightning protection system gives a lightning strike a controlled path to earth so the energy bypasses the building's structure, services, and occupants. It comprises air terminations at roof level, down conductors routed to earth, test joints, and earth electrodes, with bonding to metallic services so no dangerous potential difference can develop between them during a strike.

BS EN 62305 is the governing standard and it drives both the design and the inspection regime. Systems are classified by protection level, determined by a risk assessment reflecting the building's exposure, use, and contents. That classification sets the inspection interval, which is why 'annual' is a reasonable default but not a universal answer — higher protection levels and systems in corrosive environments are inspected more often.

From an FM point of view lightning protection is a quiet asset: it does nothing visible, it is often the responsibility of nobody in particular, and its condition degrades invisibly through corrosion at buried joints and mechanical damage during roof works. The single most common finding is not a failed test but a conductor disconnected by another trade and never reinstated.

This checklist is one of 17 in our electrical maintenance checklists, covering distribution boards, switchgear, generators, UPS, solar PV and EV charging — inspection, testing and thermographic checks.