8D Method: How to solve problems?

Introduction

In today's competitive world, effective and efficient problem-solving is crucial. The 8D (Eight Disciplines) method is one of the most widely used approaches to problem-solving across various industries. It is most common in the manufacturing sector.

This article offers an overview of the 8D method, covering its history, structure, benefits, drawbacks, and a brief mention of other problem-solving techniques.

History of 8D

The US military established some basic concepts related to a structured approach to problem-solving in 1974. They issued a standard MIL-STD-1520 "Corrective Action and Disposition System for Nonconforming Material." It required contractors to properly handle nonconforming products (rework, repair, use-as-is, scrap, MRB) and manage corrective actions[1]. The standard was finally canceled in 1995[2]. Note that the standard did not include a description of the 8D Method, although it could have provided a basis for further work on how to solve problems.

In 1987, Ford Motor Company developed an 8-part problem-solving method in a training manual called "Team-Oriented Problem Solving," hence we sometimes encounter the term TOPS 8D or more commonly as 8D.

In the mid-1990s, Ford updated the 8D method with an additional "D0" discipline. This expanded approach is now recognized as Ford's global standard, known as Global 8D (G8D).

8D Method

The 8D method is structured around eight disciplines, each addressing a specific problem-solving aspect. The most common descriptions of the eight disciplines are:

• D1: Establish the Team. Form a cross-functional team with the necessary knowledge and skills to address the problem.
• D2: Describe the Problem. Clearly define the problem. There are several tools, such as 5W2H, Is/Is-Not etc.
• D3: Develop Interim Containment Actions. Determine and implement immediate actions to contain the problem and prevent escalation. Interim actions are maintained until subsequent corrective actions are successfully implemented.
• D4: Define and Verify Root Cause. Use root cause analysis techniques to identify the underlying cause(s) of the problem.
• D5: Choose and Verify Permanent Corrective Actions. Develop possible corrective actions and then determine which actions will be implemented.
• D6: Implement and Validate Permanent Corrective Actions. Implement the planned actions and verify their effectiveness. If these corrective actions are effective, then the immediate actions can be removed (D3).
• D7: Prevent Recurrence. Determine measures at the management system level (processes, procedures, standards, FMEAs) that, if improved, should eliminate the risk of recurrence of problems in the future or in other processes, company facilities, etc.
• D8: Recognize the Team. Acknowledge and celebrate the team's efforts in resolving the problem.

Note: Depending on the 8D approach used, some steps may have different meanings, or there may be additional steps. For example, the Ford G8D method uses "D0 - Prepare for 8D" where "Emergency Response Action (ERA)" may be used[3].

When addressing problems, it is useful to use quality tools such as:

• Check sheet
• Ishikawa diagram
• Control chart
• Histogram
• Pareto chart
• Scatter plot
• Stratification
• Process flow chart

As part of the activities, a decision may be made to repair products. If this is the case, it is worth familiarizing yourself with the concepts of rework and repair to reduce the risk of misunderstandings with customers or suppliers.

During 7D, it is recommended to check if the PFMEA analysis or control plan needs to be updated.

8D Report

The 8D report is a formal documentation of the problem-solving process. This document is often required by customers or regulators to demonstrate that a thorough and effective process was conducted. Keep in mind that the 8D report is a summary, so other records (e.g., material studies, RCA analyses, results of experiments and various tests, etc.) should be preserved along with the report.

8D Method Pros

• Systematic Approach. The 8D method offers a structured framework for problem-solving, ensuring that all aspects of the issue are thoroughly addressed.
• Team Collaboration. By involving a cross-functional team, the 8D method leverages diverse expertise, leading to more effective solutions.
• Focus on Prevention. The method emphasizes preventing the problem from recurring, not just fixing the immediate issue.
• Documentation. The 8D report serves as a valuable reference for future problem-solving efforts and for demonstrating compliance with quality standards.

8D Method Cons

• Time-Consuming. The 8D method can be time-intensive, especially for complex problems, as it necessitates thorough analysis and detailed documentation.
• Requires Training. Effective implementation of the 8D method requires team members to be trained in its principles and techniques.
• Potential for Overcomplication. For simpler problems, the 8D method may be unnecessarily detailed, leading to overcomplication of the problem-solving process.

8D standards

• Global 8D (G8D). Method developed by Ford Motor Company.
• VDA Volume 8D. Published by the German Association of the Automotive Industry (VDA), this manual provides a comprehensive approach to applying the 8D methodology within the automotive sector.
• AESQ RM13000. This reference manual, issued by the Aerospace Engine Supplier Quality (AESQ) Strategy Group, supports the SAE AS13100 standard. It provides detailed guidelines for implementing the 8D method, specifically in the aerospace industry.

Due to the popularity of the 8D method, various modifications are present in the industry. Pay attention to the differences, as they may be a source of misunderstanding in customer-supplier communication.

Other Problem-Solving Methods

While the 8D method is widespread, there are other problem-solving approaches:

• AIAG CQI-20
• PDCA (Plan-Do-Check-Act)
• Six Sigma DMAIC
• Root Cause Analysis (RCA)
• Fault-Tree Analysis (FTA)
• QRQC
• 5-Why
• A3
• TRIZ

..and many others.

Summary

The 8D method is a practical, structured approach to problem-solving, particularly well-suited for complex issues that require thorough investigation and detailed documentation. Despite challenges such as being time-consuming and requiring specialized training, its emphasis on preventing problem recurrence and fostering team collaboration makes it an invaluable tool in quality management. By understanding and applying the 8D method, organizations can enhance their problem-solving capabilities and improve overall product and process quality.