The reliability is dependent on operational parameters, equipment integrity programs, monitoring and control of process variables and practices for managing changes. Operation parameters and control of process variables have the largest impact on reliability (as high as 60-70%). Most of the systems currently are focused on rigorous mechanical (equipment) integrity programs.
Reliability is determined by decisions made during design, engineering and construction of the facility. Equipment specifications and selection play an important role during project implementation. The approach for sparing, process monitoring/control and specification/selection of plant hardware play an equally important role.
Once the plant starts producing, operational parameters change and can have significant impact on reliability if the operation and maintenance fails to control and adjust the anticipated operating conditions as well as the asset integrity programs. This requires fundamental understanding of the technology and input of multi-disciplinary team of experts.
While it is a common tendency to think of reliability as an extension of maintenance function, the reality is that process technology experts along with other subject matter experts play a key role in solving the reliability issues in the plant.