Or PFEMA, Abbreviation for Process Failure Mode and Effects Analysis, which is a structured analytical technique used by a process responsible team/individual to identify potential failures of a process. Process FMEA helps to prioritize the necessary action to mitigate the risk.
It is a living document that should be initiated prior to process of production and maintained through the life cycle of the product.Process FMEA ?PFMEA defines the risk, analyses the effects, and evaluates each process step and assigns a risk score on a scale of 1 to 10 for the following variables:
- Severity — Assesses the impact of the failure mode (the error in the process), with 1 representing the least safety concern and 10 representing the most dangerous safety concern. In most cases, processes with severity scores exceeding 8 may require a fault tree analysis, which estimates the probability of the failure mode by breaking it down into further sub-elements.
- Occurrence — Assesses the chance of a failure happening, with 1 representing the lowest occurrence and 10 representing the highest occurrence. For example, a score of 1 may be assigned to a failure that happens once in every 5 years, while a score of 10 may be assigned to a failure that occurs once per hour, once per minute, etc.
- Detection — Assesses the chance of a failure being detected, with 1 representing the highest chance of detection and 10 representing the lowest chance of detection.
- RPN — Risk priority number = severity X occurrence X detection. By rule of thumb, any RPN value exceeding 80 requires a corrective action. The corrective action ideally leads to a lower RPN number.
How to Complete a Process FMEA
A simple explanation of how to complete a process FMEA follows below:- Form a cross-functional team of process owners and operations support personnel with a team leader.
- Have the team leader define the scope, goals and timeline of completing the FMEA.
- As a group, complete a detailed process map.
- Transfer the process map for the steps of the FMEA process.
- Assign severity, occurrence and detection scores to each process step as a team.
- Based on the RPN value, identify required corrective actions for each process step.
- Complete a Responsible, Accountable, Consulted, and Informed (RACI) chart for the corrective actions.
- Have the team leader on a periodic basis track the corrective action and update the FMEA.
- Have the team leader also track process changes, design changes, and other critical discoveries that would qualify and update the FMEA.
- Ensure that the team leader schedules periodic meetings to review the FMEA (based on process performance, a quarterly review may be an option).
