A turnaround is a highly expensive planned period of regeneration in a plant or refinery. During this time, an entire part of the operation is offline, whilst plants are inspected and revamped. Not only are the tools and labor required for executing a turnaround extremely expensive, but the revenue lost through shutting down elements of production can amount to a significant portion of an annual budget. Turnarounds often throw up more issues than anticipated, making them difficult to keep on track, and requiring very experienced managers and inspectors.