A PTW system is a formal written system used to safely control and perform certain types of jobs that are identified as potentially hazardous. It is also a means of communication between various departments, plant supervisors, operators, agencies etc. The permit to work contains acceptable information on important safety procedures as well as specific instructions on the nature, time and place of the work. to follow. Permits of work are an essential part of a safe work system to control high-risk work activities. The high-risk nature of the work is the key characteristic of this type of work, making them subject to permit control. If the work is not done properly then the lives of workers and other people may also be lost.