Many design engineers are confused about the difference between a Risk Assessment (RA) and a Failure Mode and Effect Analysis (FMEA).
When do I need which? What are they for? Do I need both? Here are some answers: The two methods are fundamentally different when looking at the approach; an RA is considered a top-down approach, where a starting point is an unwanted event, aka as hazardous event. The FMEA on the other hand is a so-called bottom-up approach, where an existing design is being analyzed for possible consequences (effect) in case of a failure, hence the name FMEA.
So when do I need which? On a new development with only some rough ideas (concept stage), you will only get all the detailed design requirements from a properly executed RA. Without a detailed design in place, no FMEA can be done. Once that detailed design is done, or during a modification of an existing design, the FMEA can be very valuable as a powerful verification method. So, do I really need to do both? Yes and no. Certain hazardous events associated with people’s behavior will simply not be identified in an FMEA. This is a very important and often underestimated fact in the Amusement Industry. Also, a RA will identify potential risks much earlier in the development process and therefore will make your entire design less expensive vs. implementing corrections needed based on the result of an FMEA. For mechanical systems, an FMEA can be very valuable where on control systems, due to strong normative requirements on functional safety, an FMEA is often just a costly redundant method.
In the not-too-far future, ADVANTIS plans to offer an FMEA plug-in as a design verification tool in order to close the loop back to the initial risk assessment and bridge these requirements to the validation phase by auto generating your acceptance test plans (FATP, SATP). If you have specific questions or requirements about FMEA contact us at info@advantis.tech
