Reliability Beyond Maintenance

Half a century ago, when Quality issues were introduced, (Juran, Demming) at first “quality” was thought of as the “quality of a product”. Soon the “quality” concept grew into “total quality”, when it was realized that to achieve product or service quality, everything in the organization has to respond to the “quality concept”.

Now a similar situation arises with the “Reliability” concept.

As soon as Management starts to realize the philosophy behind the concept it becomes wise to expand Reliability into other areas. New ideas crop up fast in the XXI Century...

Nobody will deny that both in business as in non-business environments, RELIABILITY is a key concept ! As is accountability and responsibility. It is of small comfort to know “something” functions satisfactorily if we can not RELY on it to function as satisfactorily whenever we NEED it to do so…And always when needed. The lack of reliability, no doubt, is a disturbing notion ! And such shortcoming can cause safety or environmental damages and economic losses beyond doubt not desired.

In the ‘60s Stan Nowlan and Howard Heap started the RELIABILITY notion for maintenance in the airflight industry. (1978 report commissioned to United Airlines by the US Department of Defense). In the ‘80s, John Moubray expanded the concept for its universal utilisation in industry and services wherever there are physical assets meant to FUNCTION. Machines, equipment, installations, buildings, vehicles, systems, whatever is meant to comply with certain specified functions and performance standards. Thus RCM2 was structured, the book first edited in English, 1991 and since then, translated into 12 languages and used around the globe to train thousands of RCM2 users and facilitators and giving place to many adaptions and variations all under the “RCM” umbrella.

Let us draw a parallel with the history of the QUALITY concept. When in the mids of the XX Century Juran and Demming (among others) launched massive “quality” concepts and projects, at first they were addressed to product quality. Assure along the production process of a product that the end product will fully satisfy the previously defined specifications. Very soon, this quality concept turned into the TOTAL QUALITY concept. Today, obvious to all of us, that “quality” is not only product quality, but precisely to achieve this, total quality must be enforced. Quality of process, systems, people, in fact ALL variables which influence the concept of “TOTAL QUALITY”.

Back to RELIABILITY. With the same criteria stated above for quality, we can no more restrict the reliability concept to maintenance alone! If our whole OPERATION must be RELIABLE, we must make sure that all components of the operational process are, in fact, reliable. It would help only a partial purpose to insure Maintenance Reliability alone… Checking the brakes of my car (yes, good, that is part of maintenance), but not sure if I have gas in the tank… Whoever works with knowledge and experience with RCM, will include “running out of gas” as a failure mode (for functional failure “engine stops”). But where do we establish the “border”? If we analyse this question thoroughly, we will soon discover – as happened with “total quality” – that everything affecting the final output must be challenged for reliability.

The essential “seven RCM questions” are so “common sense” that once you know them and use them, they transcend the maintenance area by themselves. Is it not the absolute starting point to ask what you want something to do if you want to ensure it does what you want it to do? The FUNCTION and its performance standards. Next, when will you say the function is not being fulfilled? When it does not do what you want it to do. The Functional Failure. And now: which is the CAUSE for that Functional Failure? The Failure Mode. And then, what EFFECT does this particular failure mode produce, if it happens? Then, the important question so as to make sure whatever solution you find will be costeffective: what is the CONSEQUENCE of the failure mode? And only after those questions, the search for the avoidance or minimization of those failure consequences. ACTIONS to take BEFORE we have to suffer the consequences. And these actions must be both “technically feasible” and “worth-while doing”. And finally, what do we have to do if no proactive actions are found when we ask the previous question.

A simplified example, perhaps farfetched but nevertheless a valid illustration of the idea:

Failure

Of course we must remember that we must list all the Functions, that there will be several Functional Failures for each Function and several Failure Modes for each Functional Failure. A thorough example analysis would exceed the scope of this paper. What we do want to propose, is the feasibility of the philosophical approach to reliability beyond maintenance!

Henry Ellmann, February 2009