DFMEA Guide: Design Failure Mode and Effect Analysis

by Bruno Medici | October 06, 2022 | Reading time: 7 minutes

What Is DFMEA?

What does DFMEA actually mean? How is DFMEA linked to FMEA? And how do you calculate RPN? These are just some of the most common questions to ask related to creating a DFMEA. To answer them, let’s answer first what the meaning of DFMEA is.

Design Failure Mode and Effect Analysis (DFMEA) is a framework of procedures and interventions to create the best final design of a product or service. It’s used to identify and resolve problem areas, failures, and red flags in a company’s design process or workflows for its products or services.

The final report after this analysis will then serve as a reference playbook for employees and stakeholders to go back to in order to avoid repeating the failures or mistakes.

What makes DFMEA vital in the manufacturing or service industry is the fact that it dramatically reduces the risk and failure exposure of production. This is even more important when the company belongs to an industry where the risk of failure is high, and avoiding accidents can make or break a company.

Why Is DFMEA Important? How Does It Benefit Me?

Basically, a DFMEA is important because it allows company owners, managers, and employees...:

• To save money and time by empowering the team members to understand their workflows better. When they know their weak points and understand the design of their systems competently, they can remove redundancies and improve turnaround time.
• To protect the employees’ career bottom line by enhancing the safety components of the procedures to reduce accidents. This is especially relevant in the world of manufacturing. The safer the company or facility, the lesser cost will there be on insurance claims and incident expenses.
• To boost the reputation of managers by speeding up company growth and reaching high-margin targets of companies faster. This is thanks to improved workflows that can create high-quality products at the lowest timespan. This is useful when a robust design process will dictate a product’s cost and development time.
• To reduce redundancies and inefficiency in the supply chain that can cost the job security of employees and upper management. This is partly because of the removal of partial, full, and degraded failures in all the processes related to production or delivery. This is most useful in companies when unintentional failures have a chain reaction that derails company targets.

In this article, you will learn:

1. How to conduct DFMEA in 5 steps

2. The industries where DFMEA is vital

3. The most common DFMEA mistakes to avoid

4. The time-tested tips and best practices for executing powerful DFMEA systems

STEP BY STEP: How to Conduct DFMEA in 5 Steps

If you want to know how you can conduct a DFMEA, you should first know that the format varies according to the industry. From automotive to aerospace, the procedures will also only be effective if they’re conducted in an organized, seamless, step-by-step process.

Regardless of the industry, the steps below already contain the core principles needed to conduct an effective DFMEA:

Step #1: Map Out The Process

The first step to creating an effective DFMEA process is to map out the direction or function of the design. This can best be initiated using a detailed flowchart or diagram on what needs to be done, to be avoided, and a map of the possible variables that can lead to an expected course not panning out.

The diagram should first indicate the scope, functions, set of requirements, and tasks. Next, the ways in which the failures were observed in the entire production or delivery should be added— from input to quality inspection. When the entire scope is placed in a diagram, you can now see a better picture of the steps to be placed in the DFMEA to use it as an effective risk management tool, including the time frame each step can be completed.

Step #2: Find The Common Causes of Failures and Analyze Their Effects

The failures of the company usually start with recurring mistakes in the workflows. When these common causes are identified, preventive measures can be installed to limit the constraints and mitigate the damage. For example, if the product is to create software, malware attacks that recur regularly can have their damages mitigated when the common causes are ruled out and addressed.

Only after the failures are identified can it be the best time to gauge the severity of potential effects and damage of failure.

Important variables to consider in this step include the severity of the consequences of the failure, damage, or harm; their underlying causes (such as deficit in knowledge, system malfunction, and over-optimization); and a granular calculation of why such barriers occurred.

The more complex and inter-connected the deliverable is, the more likely can the variables cause inefficiencies, and all the more should the DFMEA be chiseled into workplace inspection templates.

Step #3: Install Control, Corrective and Preventive Measures

This is the step where the current and potential failures are now resolved and corrected. To prevent their recurrence, preventive measures must be added as an important component. It’s important to make sure all the measures are comprehensive and not taking shortcuts. The control measures must be existing procedures that help your company recognize failures accurately and quickly before implementation of the final design.

As a result, quality inspections, visual audits, customer reviews, and durability assessments must be done here, with an added numerical value or percentage on the likelihood of these failures to recur. For example, a number 1 can be assigned to control systems that can highly detect a failure cause, while a number 10 will be assigned to control procedures that may be unable to detect causes while the programs are occurring.

Step #4: Execute Maximum Rigorous Evaluation

This is the step needed to brainstorm ideas to evaluate the solutions to all the failure modes. By reviewing existing data and analysis reports, the quality manager may be able to scale and grow the company through scalable strategies. It’s important in the evaluation stage to consider all the potential blindspots that may render the solutions ineffective should the incidents repeat.

Step #5: Continually Improve The System By Deriving the Risk Priority Number (RPNs)

The improvement of the design process can be made more efficient with the right RPN to calculate the statistics and probability of each risk recurring. Industry experts established that you can derive the right RPN by following this formula:

RPN = Severity x Occurrence x Detection.

What is RPN in DFMEA?

The RPN in an effective DFMEA analysis is the number to be calculated in order for teams to identify which design failure should be fixed first. You also need an RPN to make sure that the depiction and calculation ability of your DFMEA process is robust.

You also need to make sure that you derive the right number from the different failure modes that you have, according to an adjustable set of criteria. To do this, you need to make sure that you have the right predetermined RPN and social value in your decision-making process.

To get an accurate, granular RPN for a project, important variables to consider include:

• Stringency of the failure effect (SEV)
• Frequency of failure occurrence (OCCUR)
• Detectability/preventability (DETEC)

The scale for these variables can be 1 to 10, with the former indicating the lowest probability, and the latter the highest. By multiplying SEV, OCCUR, and DETEC, you can now have the RPN to underscore whether the production process is high or low risk.

USE CASES: Where is DFMEA Used?

DFMEA is such an effective multi-purpose optimizer that it can be applied across almost all major industries. The main reason is that DFMEA has already proven results. It’s already proven effective in helping products scale with their design at the lowest chances of failure. Products are already launched with its help by giving their failures the most reduced severity using accurate detection scores and preventive measures.

These are the major industries where the use of a DFMEA can have dramatic results:

• Agriculture
• Aviation
• Cleaning Service
• Community Services
• Construction
• Education
• Emergency Services
• Facility Management
• Financial Services
• Food & Hospitality
• Health Services
• Horticultural
• Human Resources
• ICT-ISO Certification Applications
• Local Government
• Manufacturing
• Maritime Templates
• Mining
• Pharmacy & Chemistry
• Professional Services
• Project Management
• Real Estate
• Manufacturing
• Transport & Logistic

Next, we will answer short questions that may facilitate your understanding of this subject:

Is a DFMEA a Design Input?

The prevention and detection control tools used for creating a DFMEA analysis serve as its design input. What a DFMEA is usually going to do during the creation of a Design Verification Plan and Report (DVP&R) is to compile all the sampling sizes, criteria, protocols, and variables needed to complete the design audit.

What is the Output of DFMEA?

The most useful output of a DFMEA process to any business is the creation of a system of solutions to improve facility operations. From step-by-step actions to the creation of checklists to reduce product design failures, DFMEA can deliver form-fitted solutions applicable across scales and industries.

What is the Difference Between DFMEA, PFMEA, and FMEA?

DFMEA and Process Failure Mode and Effects Analysis (PFMEA) are varieties or types of FMEA, where the latter stands for Failure Modes and Effects Analysis. FMEA is an investigative intervention to address any asset, product, or even service failures across all industries and mitigate their consequences.

In other words, FMEA is a core of industry principles from which DFMEA and PFMEA get their roots. PFMEA helps in eliminating potential failures in the operations of facilities, while DFMEA analyzes potential failures at the development of the design stage. Both, however, help in dramatically reducing operating costs.

For more information about their similarities and differences, visit HERE.

Who Is Responsible for DFMEA?

An assigned product design engineer is the main party responsible for a DFMEA. The assigned person will then be on the level with a cross-department team, who will help in conducting important DFMEA tasks, including design creation, testing, supplier quality inspection, product quality audit, and logistics.

What does the DFMEA process focus on?

The main focus of a DFMEA is on the reduction of the risk of product failure in any facility or company. It’s also designed to increase profitability and lower production costs by avoiding product recalls or relapses. To do this, it’s necessary for the DFMEA engineer to design both strong, powerful detection and prevention controls at the highest quality possible.

EXPLAINED: What are The Most Common DFMEA Mistakes I Need to Avoid?

It can’t be stressed enough how important is a DFMEA to ensure that negative design problems are resolved before the final product launch. To ensure consistent success in product design launches, create a strategy that avoids such common DFMEA mistakes:

1. Lack of Proper Boundaries Between Departments

It’s a common mistake that organizations and inspectors fail to install the right boundaries between departments analyzing the design process. The overlap between teams and quality managers can hamper the effectiveness of DFMEA. As a result, deliverables are derailed and departments fail to prioritize the important projects first.

With the help of a DFMEA, boundaries can be established and production waste can be eliminated. Management can now focus on evaluating potential setbacks to operational processes that disrupt deliverables. This can then help maintenance departments prioritize measures by having more accurate asset breakdowns because of the boundaries.

2. Overwhelming Tasks

DFMEA is proven to decrease production costs, eliminate production waste, and reduce downtime, but only when done right. Another problem area in any DFMEA example is when the management assigns a third party overwhelming tasks. When this happens the effectiveness of reducing downtime of processes and delivery will be negatively affected.

When the DFMEA engineer in charge is too overwhelmed, they’re more likely to skip vital failure detection methods and misunderstand important objectives.

When problematic products end up recalled, not only does this cost the company redundancy, but it results in delayed growth. By not overwhelming the officer with DFMEA tasks, programs that help prevent such issues become more potent. They become more effective in prioritizing mitigation actions to reduce the occurrence and severity of multiple failure modes.

3. Lack of Foresight

Multiple DFMEA examples will already show that regardless of how rigorous the analysis is, things can still go south. This is usually the case when the execution of the design solution is already too late. The intervention is already initiated when the problem areas are already too big, and too costly to fix. To avoid this roadblock, it’s important to avoid considering a DFMEA as just an expensive optional strategy. It should be a primary risk-reduction plan before the product design phase.

Lack of foresight can be the prime reason why the process of design control becomes inferior. This can be a result of when auditors skip procedures in cause and effect separation. Lack of control plans in place can also hinder such a course of action.

4. Complacency

When system functions in the DFMEA already work well, there’s a high tendency to be complacent. This is where requirements can be often tampered with design flaws are taken for granted, and input/output ranges are not measured right. This can often result in mistakes and failures occurring again and non-compliance penalties begin to issue, which can cause the company ridiculous sums of money. As a result of complacency, most companies may identify only the problems, but never the solutions.

5. Wrong Causal Attribution

Another common mistake for beginners is when teams rank criteria too closely and assign the wrong cause of a failure. To avoid this, there should be a more rigorous investigation of the identification process of the failure modes. Stipulating causes as specific and detailed as possible can also help solve this mistake.

SIMPLIFIED: Tips and Best Practices to Execute An Impactful DFMEA

You're probably thinking: "How could a minor design error affect the company’s performance?" After all, if you're working in this industry, it's likely that you're very familiar with the ins and outs of good design.

To avoid the costly mistakes in complacency and faulty execution of a DFMEA, here are some dos and don'ts, safety tips, and best practices for quality managers and employees to follow:

1. Find a reliable software or checklist maker that can help centralize the streamlined process. Organizing all design-related information with advanced software or a checklist template maker can make a huge difference in reducing bottlenecks in DFMEA. Even with zero training, a powerful DFMEA checklist or app can help even new hires create their own audits failure-free.Many DFMEA examples will show that such a tool helps employees feel comfortable creating, joining, contributing, and resolving design failure reduction programs anywhere, anytime.
2. Simplify the Severity Ranking System for every standardized design failure mode and effect analysis. Subsystems and their components are complicated enough for your stakeholders, so to make your DFMEA analysis effective, you should make them as simple as they can be.
   For example, when doing your ranking in your failures modes, you can simplify by making three categories:
   • 1-4: This could be for failures or risks of slight annoyance but don’t affect the whole design.
   • 5-7: This category could be for failure modes that put the main functions at risk.
   • 8-10: This category could be for urgent, serious failures that have non-compliance penalty risks and so must be resolved in the quickest time.
   
   
3. Categorize the failure modes according to your business’ unique structure. Full failures could be for modes that already cripple the entire system where the facility operations cannot function until the issue is fixed. Partial failures could be those that limit the operations of an asset. Intermittent failures could be recurring, irregular errors with unpredictable but minor harm.
   Degraded failures are for those affected by wear and tear factors. You may label unintentional failures as those failures that are resulting from other facilities’ components.
4. Use DFMEA for business goals relating to lowering costs. When downsizing, cost-cutting, or resolving products that are being recalled, make DFMEA the main strategy to resolve the issues. Integrate this as the solution in the creation of realistic solutions that will urgently fix your company’s cost problems.
5. Conduct DFMEA in the initial phases of product design. This is to ensure that employers can avoid expensive mistakes later on rather than trying to solve them after the expensive incidents happen. Not only can you maintain high-quality design this way, but you can also reach business or career goals faster. Ideally, start the DFMEA creation alongside product design and before prototype design.
6. Recalculate the RPN regularly. This means you need to treat your DFMEA as a dynamic, ever-changing entity whose severity, occurrence, and detection ratings for the failure modes can rapidly change at the onset of new variables.
7. Always do user-generated assessments. No matter how small the design problem can be, it could still dictate the success of your final product, especially if these errors accumulate and inconvenience customers. Harvard Business Review even shows that companies with seamless customer experiences lead to more word-of-mouth marketing and loyal employees, followers and supporters that can skyrocket sales. As a result, these brands lead in brand name recall, profit rate, and survivorship.
   Some useful sources of quality user reviews from DFMEA examples can be: customer complaint records, warranty claims, social media comments, and tangible assets, such as recalled products, scraps, hold tag audits, and returned receipts.

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Bruno Medici

Bruno, who received his journalism degree in Madrid (UCM), is specialized in objective information after working for international news agencies. He is also dedicated to photography, literary writing and communication consulting among many interests. In addition, these include his passion for the “industrial world” and production philosophies, portrayed in his articles in Lumiform.