A process failure mode and effects analysis. A team goes through a manufacturing process step by step, lists how each step could fail, what the effect would be and what could cause it, rates each for severity, occurrence and detection, and acts on the highest risks before they turn into defects.

How do you calculate RPN?

The risk priority number is severity × occurrence × detection, each rated from 1 to 10, so it runs from 1 to 1,000. The Excel version works it out before and after the action.

What is the difference between RPN and action priority?

The AIAG and VDA FMEA handbook published in 2019 replaced RPN with action priority (AP): a high, medium or low rating read from tables that give severity the most weight. Many plants still use RPN. This template has a column for each, so use the one your customer asks for.

What is the difference between a PFMEA and a DFMEA?

A design FMEA looks at how the product's design could fail. A process FMEA looks at how the manufacturing or assembly process could fail to make the part as designed. This template is for the process.

How often should a PFMEA be updated?

Whenever the process changes, a new failure turns up in production or at a customer, or an action is completed and the line is rated again. A PFMEA that is only opened before a customer audit soon stops matching the real process.

Free template

PFMEA template (process FMEA)

A process FMEA (failure mode and effects analysis) is a team's step-by-step look at how a manufacturing process could fail, what each failure would do to the customer, the next process or the operator, and what could cause it. Each line is rated from 1 to 10 for severity, occurrence and detection, the risk priority number (RPN) is severity × occurrence × detection, and the team acts on the biggest risks before they turn into defects. This template has the standard columns, from the process step to the current prevention and detection controls, an RPN and an action priority (AP) column, the recommended action with an owner and a date, and the ratings again after the action. Page 2 has a general rating guide.

Free to use: print it, copy it and edit it for your team. Enter your name and work email once to download.

Page 1 of the PFMEA template: header fields for process, part, FMEA number, team and dates, a key to S, O, D, RPN and AP, and a table with columns for process step, failure mode, effect, severity, cause, occurrence, prevention and detection controls, detection, RPN, AP, recommended action and the ratings after action. — Process step to effect and causeS, O and D ratingsRPN and APPrevention and detection controlsActions, owner, dueRatings after actionRating guide

When to use it

When to use a PFMEA template

Before a new process, line or product goes into production, so the risks are handled before the first part ships.
When a process changes: a new machine, material, supplier, fixture or cycle time.
After a customer complaint or a serious internal defect, to add the failure that was missed and check similar steps. It is part of D7 of an 8D.
Before writing or updating a control plan, which takes its checks from the high-risk lines of the FMEA.
Not as a one-person desk exercise: it needs the people who run, maintain and inspect the process.

How to fill it in

1
Set the scope and the team
Write the process, part and team in the header. Bring an operator, a maintenance tech, a quality engineer and the process engineer, and have the process flow in front of you.
2
List the steps and how each could fail
Take the process one step at a time. For each, write the ways it could fail to do its job: too big, too small, missing, wrong way round, contaminated, not done.
3
Write the effect and rate severity
What happens to the customer, the next step or the operator if the failure gets through. Rate it 1 to 10 with the guide on page 2.
4
Find the causes and rate occurrence
For each failure mode, the causes that could produce it, one per line. Note today's prevention control and rate how likely the cause is to happen.
5
Note today's detection and rate it
How the failure or its cause would be caught today, and how likely that is before the part leaves the process. A high number means it would probably get through.
6
Work out the RPN and choose actions
RPN = S × O × D. Deal with every severity of 9 or 10 first, then the highest RPNs. Give each action an owner and a due date. The Excel version calculates the RPN and flags the high ones.
7
Rate it again after the action
Once the action is in, record what was done and rate S, O and D again. Carry the new controls into the control plan and the work instructions.

A filled-in example

Illustrative, not a benchmark

An example: one line of a process FMEA for the crimping step on a hose assembly.

Failure mode: crimp diameter too large. Effect: the joint leaks at the customer. Severity 8.
Cause: the setup sheet has no crimp diameter for the new die. No prevention control. Occurrence 5.
Detection control: a leak test on one part per batch. Detection 6. RPN 8 × 5 × 6 = 240.
Actions: add the diameter to the setup sheet with a first-piece check, and leak test every part in line. Owner and due date set.
After the actions: severity stays 8, occurrence 2, detection 3. RPN 48.

The RPN fell from 240 to 48, but severity is still 8 because a leak would still reach the customer. The line stays in the FMEA, and the first-piece check and the in-line leak test go into the control plan.

Common mistakes

Chasing the RPN number
An RPN of 120 can be 10 × 3 × 4. Deal with high severity whatever the product, and do not set a pass mark that hides it.
Lowering severity on paper
Severity only comes down when the design or the process changes the effect. Better inspection lowers detection, not severity.
Filling it in alone
An engineer writing the FMEA at a desk misses the failures the operators and maintenance see every week.
Adding inspection as every action
Extra checks raise the cost and still let the cause happen. Look first for actions that prevent the cause, such as a fixture or a poka-yoke.
Writing it once for the customer
An FMEA that is not updated after changes and complaints stops matching the process. Review it whenever either happens.

Download the template

Free to use: print it, copy it and edit it for your team. Enter your name and work email once to download.

Run this template in LeanSuite

In LeanSuite defects are logged as tags from the floor, ranked in the QA Matrix with an AA, A, B or C priority, and systemic ones become CAPA projects with approvals, root cause analysis and an action plan.

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