The FMEA methodology is strategically divided into two complementary areas. Design FMEA (DFMEA) focuses on product design, ensuring that functional requirements are met under all operating conditions. Process FMEA (PFMEA), on the other hand, evaluates the manufacturing cycle, ensuring that the production sequence is capable of meeting design tolerances. The structured integration of these two levels ensures that the product is born solid and manufactured without deviations.
For decades, the RPN (Risk Priority Number) index was the gold standard for risk classification. Today, new international standards (such as the AIAG-VDA manual) introduce the concept of Action Priority (AP). This approach goes beyond the mere multiplication of factors, giving greater weight to the Severity of the effect and establishing incontrovertibly which corrective actions must be implemented first.
FMEA analysis reaches its full potential when translated into operating procedures. The preventive actions identified by the PFMEA converge directly into the Control Plan, the dynamic document that instructs business processes on control methodologies, inspection frequencies, and reaction plans. In this way, risk engineering becomes a daily operational standard.
While FMEA takes a Bottom-Up approach — analyzing individual components to assess their impact on the system — Fault Tree Analysis (FTA) works Top-Down. Starting from an undesirable critical event, FTA uses logic gates (AND, OR) to identify all combinations of simultaneous failures capable of generating it. The combined use of FMEA and FTA provides an absolute guarantee on the engineering robustness of any complex system.