It is imperative that all lightning protection systems are inspected and tested at least once a year. It is part of BSEN 62305 and Electricity at Work Regulations – a requirement of British and European Standards. But the date of inspection should vary to allow for different climatic conditions to be considered for instance earth readings (for resistance) can and often rise in a period of little rain because the ground has dried out, thereby affecting the data recorded. Along with these reasons are the simple fact that the materials used for a lightning protection system can corrode and cease to be effective over a period of time.
