Sigma Magic Help Version 15

Failure Modes & Effects Analysis (FMEA)

Overview

FMEA is used to proactively plan for risks and take actions to reduce the risks. For any product or process, FMEA can be used to prioritize the risks by ranking each risk on three categories - severity of the risk, the occurrence of the risk, and the detectability of the risk. The severity is determined by understanding what the effect on the customer is if something goes wrong with the product or process. The occurrence of the risk is determined by how often a cause of the risk occurs. The detection of the risk is determined by whether we can catch the risk before it is too late - it gets into the hands of the customer. Each of the three ratings is done on a scale of 1-10. The multiplication of these three ratings provides the overall risk priority number (RPN). Higher the RPN, the greater the risk.

This tool can be added to your active workbook by clicking on Project and then selecting Failure Analysis > FMEA.

Inputs

Click on Analysis Setup to open the menu options for this tool.

Setup

A sample screenshot of the setup menu is shown below.

1	Template Type: Specify the type of template you would like to use for FMEA. Two options are available: Option Description Basic Uses an basic FMEA template. Standard Uses the new AIAG-VDA FMEA template.
2	Num Rows: Specify the number of rows for the FMEA template. This information is used to format the worksheet.
3	FMEA Type: Enter the type of FMEA you are creating. Note that the rating scale and action priority will change based on the FMEA type. Option Description Design FMEA Address potential failures associated with product design that could cause product malfunctions, shortened product life or safety hazards while using the product. Process FMEA Process FMEA uncovers potential failures that can impact product quality, reduce process reliability, cause customer dissatisfaction or create safety or environmental hazards. System FMEA System FMEAs are used to analyze a compilation of subsystems. The focus is on system related difficiencies such as integration, interactions, interfaces between subsystems, interactions with surroundings, interaction with workers etc.
4	Priority: Specify how you want to identify the high risk items for your failure modes. Two options are available: Option Description Action Priority Uses an action priority table (new AIAG-VDA FMEA process). RPN Score Use a Risk Priority Number to determine high risk items in your document.
5	Display Elements: Specify the elements you want to display on the FMEA worksheet. The available options are: Option Description Structural Analysis Display the columns related to structural & functional analysis. Structure analysis is used to identify and rbeak down the process into sequential steps. The functional analysis analyzes each element in terms of its function and corresponding requirements. Failure Analysis Display the columns related to failure analysis. The failure analysis investigates the modes of failure, the effects of the failure and the causes of failure. This is selected by default. Risk Analysis Display the columns related to risk analysis. The risk analysis quantifies the risk in terms of the degree of severity, occurrence, and detection. This is selected by default. Risk Optimization Display the risk optimization columns. This are actions you would take to address the high risk elements when you perform the FMEA analysis to improve risk and customer satisfaction.
6	View Example: Click on this button to open the example file. You can view the example to get an idea of how to fill out this tool or you can use the example as a starting point and modify it to meet your project needs.
7	Help Button: Click on this button to open the help file for this topic.
8	FMEA Setup: Click on this button to open the FMEA rating scales. You can use this button to specify both the RPN scale and the Action Priority scale.
9	Cancel Button: Click on this button to cancel all changes to the settings and exit this dialog box.
10	OK Button: Click on this button to save all changes and compute the outputs for this analysis.

FMEA Setup (RPN)

A sample screenshot of the ratings scale setup menu for RPN is shown below.
Scroll through the page to find the ratings scales for each category. There are three sections for the RPN scale:

Option	Description
Severity	Specify the rating scale for Severity Scores on a scale of 1-10
Occurrence	Specify the rating scale for Occurrence Scores on a scale of 1-10
Detection	Specify the rating scale for Detection Scores on a scale of 1-10

1	FMEA Type: Specify the type of FMEA for which you want to provide the rating scale. There are different rating scales for each type of FMEA design. Option Description Design Specify the rating scale for Design FMEA Process Specify the rating scale for Process FMEA System Specify the rating scale for System FMEA
2	Scale Type: Click on the RPN button to open the RPN scale.
3	Scale Descriptions: Specify the verbiage for each of the severity, occurrence, and detection levels. These will be displayed to the user when they fill out the FMEA so that they have a basis for selecting a rating for each element of their FMEA.

FMEA Setup (Action Priority)

A sample screenshot of the ratings scale setup menu for Action Priority is shown below.
The Priority Scale table provides a mapping between the Severity, Occurrence, and Detection scores with an Action Priority number. The severity, occurrence, and detection are mapped on a scale of 1-10 while the action priority is mapped as L (Low), M (Medium), and H (High) risks. You need to reach each element of this scale row-wise. Note that you can specify a range of ratings such as 3-5 for all ratings between 3 and 5 inclusive. If you only want to use a single value, just specify a single value (like 5).

1	FMEA Type: Specify the type of FMEA for which you want to provide the rating scale. There are different rating scales for each type of FMEA design. Option Description Design Specify the rating scale for Design FMEA Process Specify the rating scale for Process FMEA System Specify the rating scale for System FMEA
2	Scale Type: Click on the Action Priority button to open the Action Priority scale.
3a	Severity Rating: Specify the severity rating. For example, the first row applies to a severity rating of 9 or 10.
3b	Occurrence Rating: Specify the occurrence rating. For example, the first row applies to a occurrence rating between 6-10. This means it applies to all scores of occurrence 6, 7, 8, 9 or 10.
3c	Detection Rating: Specify the detection rating. For example, the first row applies to a detection rating betwen 1-10. This means it applies to all values of detection ratings.
3d	Priority Rating: Specify the priority rating that should be mapped for each row. For example, the first row maps to a high priority. Repeat this process for all values of severity, occurrence, and detection so that there are no gaps. This means no matter what value of severity, occurrence, or detection the user enters, the software should be able to use this table to determine an action priority score ratings.

Worksheet

Enter the following information in the worksheet:

• Enter a header for the FMEA on row 4. The header typically contains the name of the company, product, team members, team leader, the ID number for the FMEA document, creation date, the revision date of the document, location of the product, names of the customers, etc.
• Enter a unique issue number for each issue identified on this document for tracking purposes.
• Structure & Functional Analysis Enter the focus element that this FMEA will focus on and one element higher and one element lower than the focus element. This is based on the scope that you have defined for your FMEA exercise. Enter the function and or requirements for each of the structural elements. A clear description of the functions and requirements will help you identify the failure modes.
• Failure Mode Identify the different modes in which the failure can happen. There may be multiple failure modes for each step / structural element within your process.
• Failure Effect Identify the impact of the failure either on the upstream customer or the end-user of the product or service. The failure effect will be used to quantify the importance of this failure mode.
• Failure Cause Identify the cause of the failure. Note that there may be multiple causes for a given failure mode. Try to brainstorm and identify all possible causes.
• Risk Analysis In this section quantify the failures on a scale of 1-10 for Severity of the failure effect, Occurrence of the failure cause, and Detection of the failure before it is too late. Before you come up with these ratings, it may help to document what are the existing controls in place to either prevent or detect the failure cause/effect.
• Risk Optimization For those risks that have a high Priority (either based on Action Priority or RPN scores), you need to come up with an action plan to address the risks. Identify the actions your team will take to address the risk. These actions could be either the improve prevention and/or detection. The actions need to have a clear owner, due dates, and the team should track and complete the option action items. By using the proposed actions, we need to track what the updated Severity, Occurrence, and Detection numbers will be and recompute to Priority numbers to see if a reduction has been made to the risk for this product/process.

Checklist

If you click on the Checklist button, you will see the following dialog box. The checklist contains a few pointers on things you need to pay particular attention to while performing this analysis. The checklist has been derived from experience working on past projects. Not all the checklist items need to apply to you. However, you should carefully review the checklist and apply any recommendations that make sense for your project. Make sure to read each checklist item and mark it as completed after you have read and taken actions as appropriate for your project.

Charts

If you click on the Charts button, you will see the following dialog box.

0	Pick Charts: Specify the charts you would like to generate for this analysis.
1	Title: The system will automatically pick a title for your chart. However, if you would like to override that with your own title you can specify a title for your chart here. Note that this input is optional.
2	Sub Title: The system will automatically pick a subtitle for your chart. However, if you would like to override that with your own subtitle you can specify a subtitle for your chart here. Note that this input is optional.
3	X Label: The system will automatically pick a label for the x-axis. However, if you would like to override that with your own label for the x-axis you can specify a different label here. Note that this input is optional.
4	Y Label: The system will automatically pick a label for the y-axis. However, if you would like to override that with your own label for the y-axis you can specify a different label here. Note that this input is optional.
5	X Axis: The system will automatically pick a scale for the x-axis. However, if you would like to override that with your values for the x-axis, you can specify them here. The format for this input is to specify the minimum, increment, and maximum values separated by a semi-colon. For example, if you specify 10;20 then the minimum x-axis scale is set at 10 and the maximum x-axis scale is set at 20. If you specify 10;2;20, then, in addition to minimum and maximum values, the x-axis increment is set at 2. Note that this input is currently disabled and you will not be able to change this setting.
6	Y Axis: The system will automatically pick a scale for the y-axis. However, if you would like to override that with your values for the y-axis, you can specify them here. The format for this input is to specify the minimum, increment, and maximum values separated by a semi-colon. For example, if you specify 10;20 then the minimum y-axis scale is set at 10 and the maximum y-axis scale is set at 20. If you specify 10;2;20, then, in addition to minimum and maximum values, the y-axis increment is set at 2. Note that this input is optional.
7	Horizontal Lines: If you want to add a few extra horizontal reference lines on top of your chart you can specify the values here. The format for this input is numeric values separated by semi-colon. For example, if you specify 12;15 then two horizontal lines are plotted at Y = 12 and Y = 15 respectively. Note that this input is optional.
8	Vertical Lines: If you want to add a few extra vertical reference lines on top of your chart you can specify the values here. The format for this input is numeric values separated by semi-colon. For example, if you specify 2;5 then two vertical lines are plotted at X = 2 and X = 5 respectively. Note that this input is optional.

Verify

If you click on the Verify button, the software will perform some checks on the data you have entered. A sample screenshot of the dialog box is shown in the figure below. The objective of this analysis as well as any checks that are performed is listed in this dialog box. For example, the software may check if you have correctly specified the input options and entered the required data on the worksheet. The results of the analysis checks are listed on the right. If the checks are passed, then they are shown as a green-colored checkmark. If the verification checks fail, then they are shown as a red-colored cross. If the verification checks result in a warning, they are shown in the orange color exclamation mark and finally, any checks that are required to be performed by the user are shown as blue info icons.

Outputs

Click on Compute Outputs to update the output calculations. The software will update the Priority scores based on the requested methodology (RPN or Action Priority). It will also check if you have correctly entered the information on the worksheet. A sample screenshot of the worksheet is shown below. If there are no problems with your FMEA analysis, it is indicated as such in the conclusion box. If there are any problems with the FMEA, a dialog box displays the problems identified on the FMEA. The items checked by the algorithm are missing fields in the form and whether you have defined sufficient actions to reduce the risk.

The FMEA will also plot the overall risks on a bar chart or a histogram for the current risks and the updated risks after completion of the recommended actions. Ideally, we should be a reduction in risks and as more and more actions are addressed, we should monitor and report a reduction of risks over time.

Notes

Here are a few pointers regarding this analysis:

• It is recommended that you use Action Priority to prioritize your risks. If the Action Priority is either a High or Medium your team must take actions to address the risk element. You can choose to ignore the Low-risk items.
• You can also choose to use RPN scores to prioritize your actions. Sigma Magic will flag all RPN scores greater than 125 as requiring actions. If an RPN number is greater than 125, it will expect that actions are defined to reduce the risk to less than 125. This check is only performed if you choose RPN as your prioritization method.