The boy was playing with friends, supervised by an adult, at Cherry Lane Adventure playground in Crawley on 8 April 2014.
Worthing magistrates heard that the wooden pole of the rope swing he was on broke, hitting him on the head.
He suffered serious head injuries and was airlifted to hospital and has since made a full recovery.
Glynn Hughes, a self-employed inspector accredited by the Royal Society for the Prevention of Accidents (ROSPA), was prosecuted by the Health and Safety Executive. He failed to identify the swing was rotting during a number of inspections.
HSE’s investigation found that Hughes described the condition of the swing as ‘excellent’ during an inspection in 2013. Seven weeks before the incident he reported the risk posed by the swing as ‘low’ despite him having raised previous concerns over its stability.
Worthing Magistrates’ Court heard on 11 September that thorough inspections of wooden play equipment are vital to preventing accidents. In this case HSE found the rot was foreseeable, had occurred over a long period of time and should have been spotted by the inspector and reported to the playground operator, Crawley Borough Council.
Glynn Hughes of, Walgrave Road, Old, Northamptonshire, pleaded guilty to breaching Section 3(2) of the Health and Safety at Work etc Act 1974 and was fined £1,120 and ordered to pay costs of £3,600.