The Psychology of Quality and More

Failure Mode and Effects Analysis (FMEA)

Many problems are caused by systems which fail in unexpected ways, which can result in significant costs.  A detailed analysis of the possible ways in which a system might fail, and the possible effects of these failures may thus save significant future costs.

Failure Mode and Effects Analysis (commonly called FMEA) takes the dual step of first finding out how an item can fail, and then finding what effect this failure might have. This second step thus helps to identify the importance of a failure mode, allowing identification of the key failure risks which must be addressed.

Risk is commonly identified by multiplying severity and criticality. It may also include probability, and detection assessment. One variant, called Risk Priority Number (RPN) may be calculated as a multiplication of assessed indices for Severity, Occurrence and Detection (hence RPN = S x O x D).

PFMEA stands for Process Failure Mode and Effects Analysis and applies the principles of FMEA to a process rather than a physical item.

EMEA stands for Error Mode and Effects Analysis.

See also:

Toolbook chapter: Failure Mode and Effects Analysis (FMEA)