E-Archive


Vol. 10
May Issue
Year 2009
BACK

Nadcap Column


in Vol. 10 - May Issue - Year 2009
Prevention Is Better Than Cure





FMEA stands for Failure Mode and Effects Analysis. It is a process for analysis of potential failure modes within a system for classification according to severity and/or probability of the effects of a failure in the system.

In a sense, every individual performs FMEA on a daily basis in their routine existence: in a given situation, we all weigh up what to do and what to say, judging what the outcome may be, and the potential risks involved. But in an everyday situation, it is not done systematically, and it is probably done in haste, which causes mistakes: errors of judgement.

FMEA differs from RCCA (Root Cause Corrective Action) because it represents a method of looking forward and anticipating potential issues before they occur, whereas to perform RCCA, an incident must already have happened for corrective action to be needed. Learning from past failures is a costly business: not just in terms of money but also in terms of lost time and reduced trust from your customer. FMEA is considered by some to be a more proactive, systematic way to approach processes.
To perform effective FMEA, processes must be analysed objectively to determine:

1. Severity of Consequences

The more severe the potential consequences of an occurrence, the more effort must be put into prevention. The severity of the consequence encompasses a range of possible outcomes including risk to life/ well-being, cost implications, impact on the perception of company and/or product reliability and the effect on customer relationships. Where the potential occurrence cannot be eliminated, the severity of the consequences may be reduced.

2. Probability of Occurrence

The frequency, or probability of an occurrence, is also important. For example, aviation accidents are extremely rare, with the probability of a passenger being killed on a single flight at approximately eight million-to-one. If a passenger boarded a flight at random, once a day, every day, it would statistically be over 21,000 years before he or she would be killed. So in the FMEA rating, probability would be rated low. However, because the consequences could be severe, that element would be rated higher.

3. Ease of Detection of Problem

The ease with which the issue can be detected is also important: if it is very difficult to detect an issue, then more effort must be put into identifying it and this impacts on the effectiveness of FMEA.
Each of these factors is given a rating which, when multiplied, provide the RPN (risk priority number), which helps to identify the type and urgency of the action required. But there’s another element as well:

4. Current Situation

The current situation – what is already known of the potential issue and what is being done about it – do not get a rating in the FMEA system. But it will help clarify what action needs to be taken. Hopefully, the above areas have already been identified and rated, and action/s have been determined already to mitigate the risk. But if not, this will need to be done.

FMEA is not an easy process to get right but the potential value it represents to any business in terms of cost and time savings, let alone possibly anticipating and mitigating more serious risks, is significant.

eQuaLearn is part of PRI’s Customer Solutions & Support (CS&S) initiative, which exists to provide quality customer-driven and cost-effective business solutions to continually improve organizations throughout the world.

Learn more about FMEA at www.eQuaLearn.com