A Bunbury man has been airlifted to hospital with serious injuries following an explosion at an oil refinery on Saturday night.
Police and emergency services were called to the scene at the refinery in Bunbury at around 11.20pm.
A Carey Park man in his 40s was struck by a concrete and steel door that became a projectile in the explosion.
Two officers from Bunbury Police were the first to arrive at the scene and provided first aid to the man.
Department of Fire and Emergency Services and St. John Ambulance paramedics arrived a short time later.
The man was airlifted to Royal Perth Hospital with serious injuries however his injuries are not believed to be life threatening.
Maintenance work was being conducted at the premises when the incident occurred.
Worksafe have since been notified about the incident.