Turnaround is a scheduled stoppage of part or all of a plant’s operations to allow maintenance and upgrade. The term is used mainly in process, particularly continuous process, production facilities (refinery, petrochemical plant, power plant, etc.). A turnaround has large costs and production implications, and can require weeks, months or sometimes years of elapsed time. It may involve external health, safety and environmental review. So turnarounds are planned as major projects headed by a senior manager.