The US Government standardized the process of Corrective Actions in MIL-STD-1520 (Corrective Action and Disposition of Nonconforming Material). This standard was first issued in 1974, and the last revision was Rec C, issued in 1986 and later cancelled in 1995 without replacement.
This problem-solving approach was later formalized and popularized by Ford Motors.
8D or Eight Disciplines
The eight disciplines are the eight steps of the problem-solving approach. Later, in the 8D method, step D0 was added to the process. These eight steps (and initial step zero) include:
D0 - Preparation and Emergency Response
- Understand, define and quantify symptoms
- Identify the customer and other affected parties
- Protect the customer (band-aid solution) – Use the PDCA approach
- Determine if an 8D approach is needed
D1 - Establish the Team
This is the first step in creating a disciplined approach to developing solutions. It involves establishing a team that will be responsible for resolving the issue. Typically, the team consists of 3 to 7 members. When selecting a team member, selecting individuals with different skill sets and experience is essential. Each individual should bring something unique to the table.
The team members' roles are clarified and defined during this phase, and the ground rules are set up for the team.
D2 - Describe the Problem
In this step, the team describes the problem they are trying to solve. The problem is defined in quantifiable terms. A problem statement is created that defines the scope of the problem.
The problem boundaries are also established. For example, it may be stated as "the problem is limited to the XYZ application."
The affected party reviews the problem description, and any changes are documented.
D3 - Interim Containment Plan
During this step, the team creates a containment plan. These are temporary actions to isolate the customer from the outcome of this problem. The goal of interim containment is to minimize the impact on the customer while the team works on a permanent fix.
The interim containment plan is reviewed with the appropriate departments or functions in the organization.
When developing the containment plan, consideration is given to the following:
- Benefits vs risks
- What can we do to limit the impact?
- How long does the containment need to be effective?
- Is there anything else we need to consider?
D4 - Root Cause Analysis
Root cause analysis is performed to determine why the problem occurred. The team identifies all possible contributing factors that could have caused the problem. They then analyze each factor and assign a probability to how likely it is to have contributed to the problem.
D5 - Develop Permanent Corrective Actions
After determining what caused the problem, corrective actions are taken to prevent future occurrences. This includes documenting the action(s), assigning responsibility, and implementing them.
There can be multiple root causes for a problem. Also, for every root cause, there could be multiple corrective actions. Hence the corrective actions might need to be prioritized.
D6 - Implement Permanent Corrective Actions
Once the corrective actions are implemented, the team reviews their effectiveness. If necessary, additional corrective actions are added.
Also, at this stage, evaluate containment actions and decide when these can be removed. If the problem does not disappear, reapply containment actions and revise the Corrective Action plan.
D7 - Prevent Future Recurrence
At this point, modify work processes, systems, methods, equipment and practice to prevent similar problems (in the same work area or other areas in the organization).
D8 - Recognize Contributions (Individual and Team)
This final step recognizes the contributions of individuals and teams involved in the process. It is essential to recognize the contribution of those who helped resolve the problem.
Additional Thoughts on the 8D Approach
In my experience, I've found that the 8D approach provides a good framework for dealing with complex issues. However, it's important to remember that it's just one tool among many others. There are many different ways to approach an issue.
For example, you could use the 5 Whys or the Cause and Effects diagram instead of the 8D approach. You could also use a combination of approaches.
If you're working on a small project, you may want to start by using the 5 Whys. But if you're trying to solve a large problem, you may want to use the 8D approach.
You should choose the right tool based on your situation.