Investigation of Failures

Not all equipment failures require investigation. In some cases, the cause of an equipment failure may be quite obvious. Such is the case with damage from weather-related events such as floods or tornadoes, intentional sabotage, or automobile accidents. In other cases, the equipment is not crucial to the process or it can easily be replaced with little cost or impact to production. Failure investigations are most useful when high-dollar, critical equipment fails unexpectedly and for an unknown reason. Investigative techniques vary based on the industry, environment, equipment type, and level of failure. Regardless of the investigative methodology and specific steps involved, all investigations should take a forensic approach to identifying the cause or causes of the failure. This means carefully examining the scene and looking for evidence that can provide clues into the nature and possible cause of the failure. Interviewing witnesses provides a first-hand account of how the equipment was running or what occurred as the equipment failed. It is important to document the facts and not the opinion of the workers involved. Use photos, videos, sketches, and diagrams to clearly identify the “as found” condition of the equipment. If appropriate, collect samples of process fluids, lubricants, damaged gaskets, seals, piping, and fittings. Preserve damaged equipment components so they can be analyzed. The investigator must avoid jumping to conclusions. A systematic review of the failure and evidence will ultimately identify the root causes, or reasons, for equipment failure.