Plants are subject to turnarounds (ie shutdowns) for cleaning, maintenance and inspection, typically at 4-year intervals. This is a potentially hazardous activity that normally lasts around 4 weeks. Generally, it consists of a large number of artisans (most of whom are contractors), performing a wide range of jobs, some of which are mutually exclusive due to their hazardous nature. This work has to be tightly controlled and these modules explain how that is achieved. A critical element of a turnaround is the Pre-Startup Safety Review (PSSR), which ensures that the plant is ready to be returned to operation. This is one of the key elements of OSHA’s PSM.