The Philosophy of RCM
Reliability Centered Maintenance (RCM) is a maintenance philosophy governed by a set of principles and executed by detailed methodology. It is an organized approach to building an intelligent maintenance plan. By following the principles of Reliability Centered Maintenance, you will be determining the right amount of maintenance, which is cost effective, and provides the reliability necessary to carry out your business’ mission. Reliability Centered Maintenance is a top down analysis of your operations systems and processes, with the objective of ensuring that those functions critical to your business operate as you require. In short, Reliability Centered Maintenance analyzes each system and how it can functionally fail. The effects of each failure are analyzed and ranked according to their impact on safety, mission and cost. Those failures which are deemed to have a significant impact are further explored to determine the root causes. Finally, preventative maintenance is prescribed based on established applicability and effects criteria with an emphasis on condition based tasks to help ensure the necessary reliability for your facility. Based on Fractal Solutions’ extensive experience with Reliability Centered Maintenance we have streamlined the application for peak efficiency and user friendliness.

Background
Early approaches to preventive maintenance programs were based on the concept that periodic overhauls ensure reliability, and therefore operating safety. However, tests by the airlines in 1965 showed that scheduled overhaul of complex equipment have little or no effect on the reliability of the equipment in service. These tests indicated the need for a new approach towards preventive maintenance, which was eventually developed in 1968.

Representatives of the airlines and manufacturers constituted a Maintenance Steering Group (MSG) and developed the document, MSG-1, "Handbook: Maintenance Evaluation and Program Development". MSG-1 included decision logic and procedures for developing the initial preventive maintenance program for the Boeing 747 aircraft.  Later the decision logic of MSG-1 was updated and certain detailed procedural information for the 747 was deleted. The result was a universal document applicable to the development of preventive maintenance programs on new procurement aircraft.  The product of this effort, published in 1970, is known as MSG-2, "Airline/Manufacturers Maintenance Program Planning Document".  In 1979, an Air Transport Association (ATA) task force reviewed those portions of MSG-2, which required revision for application to newly developed aircraft. The result of the task force was MSG-3, "Airline/Manufacturer Maintenance Program Planning Document”.

What Is RCM?
RCM is a set of principles and a methodology for identifying applicable and effective maintenance tasks that are necessary to achieve required reliability of systems or equipment. RCM seeks to improve the reliability of in-service systems and equipment.  It also seeks to achieve reliable operation during the design and deployment of new systems and equipment. 

RCM considers the following questions:

1. What does the equipment do?
2. What failures can occur?
3. What are the consequences of failure?
4. What can be done to prevent them?

RCM Principles
Understanding the underlying principles of RCM before commencing analysis is essential and includes the following:

1. Failures happen.
2. Not all failures have the same consequences.
3. Equipment may “wear out” or fail randomly.  Random failures are more common.
4. Preventive maintenance (PM) should preserve system and equipment function, not design characteristics. 
5. The maintenance program should keep people and the environment safe, and provide an acceptable level of operational availability at the lowest practical cost.
6. PM tasks should be “applicable”; they should work.
7. Applicable PM tasks should be “effective”; they should pay for themselves.

RCM Methodology
The RCM process devises a preventive maintenance program by evaluating the maintenance required for equipment according to its failure consequences, inherent reliability, and the cost-effectiveness of RCM recommended PM tasks.

The process determines the preventive maintenance requirements for both new procurement and in-service programs. It requires the following activities:

1. Defining systems and establishing boundaries.
2. Determining system functions and failures.
3. Identifying significant equipment.
4. Evaluating equipment failure modes and effects.
5. Evaluating equipment failure consequences.
6. Developing cost-effective maintenance tasks.