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View Full Version : Failure Mode and Effects Analysis - What if something goes wrong


Gerald_D
Wed 07 March 2007, 22:44
Quoting from Wikipedia (http://en.wikipedia.org/wiki/FMEA):

"Failure mode and effects analysis (FMEA) is a method (first developed for systems engineering) that examines potential failures in products or processes. It may be used to evaluate risk management priorities for mitigating known threat-vulnerabilities.

FMEA helps select remedial actions that reduce cumulative impacts of life-cycle consequences (risks) from a systems failure (fault).

By adapting hazard tree analysis to facilitate visual learning, this method illustrates connections between multiple contributing causes and cumulative (life-cycle) consequences.

It is used in many formal quality systems such as QS-9000 or ISO/TS 16949.

The basic process is to take a description of the parts of a system, and list the consequences if each part fails. In most formal systems, the consequences are then evaluated by three criteria and associated risk indices:

severity (S),
likelihood of occurrence (O), and (Note: This is also often known as probability (P))
inability of controls to detect it (D)
Each index ranges from 1 (lowest risk) to 10 (highest risk). The overall risk of each failure is called Risk Priority Number (RPN) and the product of Severity (S), Occurrence (O), and Detection (D) rankings: RPN = S × O × D. The RPN (ranging from 1 to 1000) is used to prioritize all potential failures to decide upon actions leading to reduce the risk, usually by reducing likelihood of occurrence and improving controls for detecting the failure"

Okay, those are a lot of big words that takes me back 20 years when I did those sort of things in the weapon industry. But the basic principles are still sound....

Have a good look at the MechMate and think carefully what could go wrong. What are the risks to the personnel, the property and the profit-line? (in that order) What do we have to incorporate in the design, in the production process, or in the operating instructions to eliminate or minimise those risks?

This thread is intended to start as a casual brainstorm of the "what-ifs".....