In order to determine what a Reliability Engineer should be, we must first look at the definition of Reliability.  Reliability can be defined as the probability that a device, system, or process will continue to perform its given function without failure for a known time in a known environment.  Based on this, the role of a Reliability Engineer can be easily defined as increasing the probability that assets will operate when required by determining and driving strategies that prevent failures.  In order to do this, the Reliability Engineer must apply analysis techniques that identify causes of failures, apply practices that prevent these failures, and determine strategies that mitigate the consequences of failures that cannot be prevented.  In other words, keep equipment and processes running well.  When they do not, find out why and do something about it.  If you cannot do anything about it, then find a way to protect the processes or mitigate the consequences.

Reliability Engineers have a strategic and tactical role within an organization.  This means being a leader, mentor, and teacher.  Developing, supporting, and maintaining a reliability roadmap in accordance with clear reliability targets that contribute to the operational goals of the company.  Support efforts that ensure the reliability, operability, and maintainability of equipment and processes.  And provide education and analysis that contributes to all of the above.

A Reliability Engineer should be many things, but definitely not a part-time position, a firefighter, parts expeditor, or reactivity manager when a failure occurs.

As an interesting exercise, write down how you define the role of a Reliability Engineer.  Ask several people to write down the top five things they believe define the role of a Reliability Engineer within your company.  The answers may be quite surprising and very telling about the real reliability culture within your company.