Failure Mode and
Effects Analysis (FMEA)
XONITEK Corporation
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FMEA…
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A way to conduct a “reliability analysis” of a product or
service
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A systematic look for:
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Function
Failure causes
Failure modes
Failure consequences
XONITEK Corporation
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Types of FMEA activities…
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DFMEA – Design analysis of:
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Components
 Subsystems
 Main systems

PFMEA – Process analysis of:
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Equipment
Scheduling
Workstations
Gages
Procurement
Employee training
 Tests
XONITEK Corporation
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FMEA Core Criteria…

Relies on valid data on either the output or process for
assessments to be valid

Documented procedures that can be validated as part of the
process help identify the source of variability…

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Random approaches to a process by employees can inject variability and
create the different outcomes.
Most effective when operating within the framework of a
sound quality system
XONITEK Corporation
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FMEA Benefits…

Improved Service Quality and Robustness…
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Reduced Customer Service Costs…
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Reduced Delivery Problems…
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Improved Service Implementation…
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Improved Safety…
XONITEK Corporation
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Creating the FMEA Team…
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Keep the team small so contribution and focus are most
important in the ultimate success of the project.
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Both the “process experts” and those “unfamiliar” with the process
will drive insight.
Don’t forget to “walk the walk” when possible to get first hand
knowledge for each member of the team.
XONITEK Corporation
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FMEA Reference Form…
Sample
FMEA
form…
XONITEK Corporation
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FMEA Header Data…

FMEA Title – Name of the System, Subsystem, Component or
Process…

FMEA Type – Circle or otherwise highlight if this is a Design or
Process project.
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Project Leader – Person responsible for the FMEA overall…
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Prepared By – Individual maintaining updates on the project.
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Project Description – Concise and easy to understand description
of the function…

Include any additional technical parameters to help define the failure
modes…
XONITEK Corporation
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FMEA Header Data…
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Dates:
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Original Date – the date the FMEA was created.
Revised Date – this is the date the input from various persons was added to
the file.
Key Date – the targeted completion date of the project.
Core Team – Members of the team responsible for the
development of the FMEA and various aspects of its completion.
XONITEK Corporation
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Current State Section…
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Item or Function – Identifies the various parts, processes or
subsystems that may fail.

Use Brainstorming to begin to identify these elements of the FMEA.
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Can be a list of separate failure modes for the same functions
May reference the upper or lower assembly impacts…
Potential Effects Mode – Describes the impact of the failure with
regards to the customer (internal or external)…
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Fishbone Diagrams may be useful to “get to” the root causes.
Potential Failure Mode – Describes how the process or design may
fail to perform with regard to design or process parameters…
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Man, materials, design, process, environment.
“If – Then” consequential statements.
Classification – Optional information, used when Govt. Regs.,
Safety Considerations or Engr. Specs exist for the product or
process…

Use a key for this field and add to the FMEA form to clarify symbols.
XONITEK Corporation
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Severity Rating Scale..

Severity Rating – Scale of 1 to 10 created by the team…
with 10 as the most severe.
Rating
Description
Definition of Failure Result:
10
Hazardous
Failure could cause bodily injury to the customer or an employee.
9
High Major
Failure defined as noncompliance with federal, state or local regulations.
8
Major
The unit becomes inoperable when failure occurs.
7
Low Major
Failure results in a high degree of customer dissatisfaction.
6
High Moderate
The failure exists in a subsystem or partial malfunction of the product.
5
Moderate
Failure is noticeable by the customer and may result in warranty or customer complaint.
4
Low Moderate
Customer can overcome failure loss with no impact to the product or process.
3
High Minor
Failure results in minor performance loss in the customers process. Customer can over
come loss by process change.
2
Minor
Failure may not be readily apparent to the customer, but would have minor affects on the
customer’s process or product.
1
Low Minor
No impact to the customer or loss of process/product capability.
XONITEK Corporation
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Current State Section…
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Potential Causes of Failure – Descriptive and comprehensive list
of all “root” causes of failure…
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Reference “Fishbone” diagram as one of the tools to find this cause…
Each “potential failure mode” may have more than one cause of failure.
Occurrence Rating – An estimate of the frequency of the failure…
derived from a team created table…

Occurrence ranking shown on next slide…
XONITEK Corporation
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Occurrence Rating Scale…
Rating
Description
Failure Rate Metrics
10
Imminent Failure
Persistent failures, >= 100,000 ppm.
9
High Major
>= 50,000 ppm < 100,000 ppm
8
Major
>= 20,000 ppm < 50,000 ppm
7
Low Major
Occurrence about 1/month or >= 10,000 ppm < 20,000 ppm
6
High Moderate
Occasional Failure of about 1 every 3 months or >= 5,000ppm <
10,000ppm
5
Moderate
Occurrence about every 6 to 12 months or >= 2,000 ppm < 5,000
ppm
4
Low Moderate
Process capable 1.33 Cpk
3
High Minor
Few failures or approaching1.67 Cpk
2
Minor
Random failure or 10 ppm or approaching 2.0 Cpk
1
Low Minor
Failure very unlikely, Cpk >2.0
XONITEK Corporation
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Current State Section…
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Current Controls Prevention – Identify the methods and testing
parameters that exist to find this failure...
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Current Controls Detection – Defines the manner that the defect is
identified…

Preference is detection by use of SPC or other testing methods.
 Discovery by failure is NOT preferred…
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Detection Rating – User defined table with assigned probabilities
and associated rankings…

Ranking table guide in next slide…
XONITEK Corporation
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Detection Ranking…
Rating
Potential of Detection
Definition
10
No Detection
Detection not possible with current systems.
9
Very Remote
Problem may occur without notice using current sampling
plan.
8
Remote
Defect can be accepted in the normal inspection criteria
sampling plan of “no defects allowed”
7
Low
Product is 100% inspected for defect during the process.
6
Moderately Low
Product is 100% inspected using “go – no go” gages.
Process has been Poka Yoked for error elimination.
5
Moderate
SPC process in place during the process and product is
also inspected off line…
4
Low Probable
SPC used and immediate response to out of tolerance
conditions.
3
Probable
Process capability has been demonstrated at 1.33 Cpk and
SPC program in place.
2
High Probability
Product 100% inspected by an automation process.
1
Absolute Detection
Methodologies created to make the failure obvious and
100% automated inspection utilized.
XONITEK Corporation
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Current State Section…
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Risk Priority Number (RPN) – A value to rank the concerns
calculated from the multiplication of the other rankings …
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RPN = Severity x Occurrence x Detection (the product of these three
values)
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Use this value to prioritize the actions and resources of the organization.
Do not overstep your resource capabilities… set a threshold of items for action and
focus on those items first.
Items with lower numbers but still have high severity must be
addressed…
Recommended Actions – Actions taken to lower the RPN…
includes Cause and Effect diagrams, control charts or other actions
necessary to reduce the risk tied to the RPN…
XONITEK Corporation
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Actions to RPN…

Develop a strategy of what items to address in what order…
Look for “synergy” of activities, where multiple problems may
overlap.
 If you can’t eliminate the issue find ways to make it easily detectable
when it occurs.
 Reduction of “severity” or “occurrence” is preferred over making the
failure more detectable.
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Document all process or design changes and their impacts as
part of the report out methodology.
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Recalculate the RPN as improvements are made to re-establish priorities.
XONITEK Corporation
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Details of filling out the FMEA…
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Person Responsible and Due Date – Enter the name of the person
who has the lead action and target date of completion…
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Actions Taken – Describe the action and implementation date…
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Severity/Occurrence/Detection – The revised values based on
actions taken…
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RPN – Revised RPN recalculated (multiply the three values:
Severity, Detection and Occurrence) from the values above…
XONITEK Corporation
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Sample Completed FMEA…
XONITEK Corporation
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FMEA –
Interactive Example
XONITEK Corporation
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