The following definitions of accidents and incidents are from the Civil Aviation Act 1990. The word 'occurrence' is used to mean any accident or incident.
Accident – means an occurrence that is associated with the operation of an aircraft and takes place between the time any person boards the aircraft with the intention of flight and such time as all such persons have disembarked and the engine or any propellers or rotors come to rest, being an occurrence in which —
a person is fatally or seriously injured as a result of —
except when the injuries are self-inflicted or inflicted by other persons, or when the injuries are to stowaways hiding outside the areas normally available to passengers and crew; or
the aircraft sustains damage or structural failure that —
except engine failure or damage that is limited to the engine, its cowlings, or accessories, or damage limited to propellers, wing tips, rotors, antennas, tyres, brakes, fairings, small dents, or puncture holes in the aircraft skin; or
the aircraft is missing or is completely inaccessible.
Incident – means any occurrence, other than an accident, that is associated with the operation of an aircraft and affects, or could affect, the safety of operation.