Maintenance Error Management for Improving Mechanical Integrity

Weak management systems lead to Human Errors that lead to accidents. The paper covers significance of maintenance errors (ME) in process industry, what and why of ME, principles of ME, extent of ME, and how to deal with ME. It proposes to have a structured program in place and what must be considered while formulating the program at a company. Limited deployment of the program at some intense maintenance environment at process facilities has shown promising results.

Maintenance errors have been among the principal causes of several major accidents in a wide range of technologies, for instance Piper Alpha disaster. For process industry, maintenance, particularly maintenance of safety critical equipment, has always been addressed as important means to prevent major accidents. Maintenance is indissolubly linked with safety in a number of ways - errors in planning, executing or checking maintenance could cause system faults; or inadequate or erroneous maintenance may also mean that existing failure or degradation is not discovered and corrected – and thereby contributes to production shut-downs, work accidents and/or major incidents. Maintenance errors not only endanger lives and assets, they are also extremely bad for business.

Process plant maintenance is a particularly challenging task due to several factors such as frequent removal and replacement of a large numbers of components, cramped, arid, poorly lit spaces and different groups work on the same item of equipment. Turnaround maintenance poses further heightened risk.

The remedy is to have a structured Maintenance Error Management Program. A wide variety of error management (EM) measures are resorted to targeting person and team, workplace and task, and organizational factors. Different types of error require different counter-measures; engineering solutions, collective mindfulness and organizational culture that is just, willing to report its unsafe acts and able to learn from them. It is not enough to deploy some tools but need to be watched, adjusted and managed on regular basis.

Aviation industry has recognized this and has mature programs in place. These could serve as examples for chemical process industry. For instance Maintenance Error Management System by Civil Aviation Authority, UK and Boeing’s human factors tool called the Maintenance Error Decision Aid (MEDA) for investigating contributing factors to maintenance errors.

Human error in process plant maintenance in the past has not been given the attention it deserves. It is a pressing Human Factors issue. Practitioners of Mechanical Integrity element of PSM need to factor its impact and develop actions to mitigate its effect. This paper would help them present the case to management for recognizing human errors in process plant maintenance as a major risk factor that ought to be controlled by having a structured program in place.