Failure mode and effects analysis (FMEA) is a widely used technique to assess or to improve reliability of products at early stage of design and development. Traditionally, the prioritization of failures for corrective actions is performed by developing a risk priority number (RPN). In practice, due to insufficient evaluation criteria specific to related product and processes, RPN is not properly evaluated. This paper reestablishes an effective methodology for prioritization of failure modes in FMEA procedure. Revised evaluation criteria of RPN are devised and a refined FMEA sheet is Introduced. To verify the proposed methodology, it is applied to RPN evaluation for motors in household appliances.