8D stands for the 8 disciplines of problem solving.
They represent 8 steps to take to solve difficult, recurring or critical problems (often customer failures or major cost drivers).
The structured approach provides transparency, drives a team approach, and increases the chance of solving the problem.
- D1: Create a Team: Gather a cross-functional team of about 5 people with product/process knowledge, and have them gather information and data related to the problem or symptom
- D2: Describe the Problem: Use the data and information to quantify and clarify the problem into a statement. Ask the 5W2H’s (who, what, where, when, why, how, and how many) for the problem.
- D3: Develop Containment Plan: Define and implement interim containment actions to isolate the problem from any customer in the future.
- D4: Determine and Verify Root Causes: Identify and verify all applicable causes and sources of variation that explain why the problem has occurred (special vs . common cause).
- D5: Verify Permanent Solutions: Collect data to confirm that the possible solutions will actually resolve the problem. Perform on a small-scale or “pilot” project first.
- D6: Define and Implement Corrective Actions: Discuss and review results, and develop plan to implement best solutions or countermeasure.
- D7: Prevention: Modify the management systems, operation systems, procedures and practices to prevent recurrence of this and similar problems.
- D8: Congratulate the team: Formally thank team members for their involvement. Use approaches that appeal to each individual member, as not everyone wants to be rewarded the same way.
Some versions of 8D include a D0, making it 9 steps (which creates a little confusion).
8D has become a standard methodology to improve processes, as it is much more prescriptive than A3 or PDCA.
The following improvement tools are often used within the 8D methodology:
- Ishikawa diagrams (Cause and Effect diagrams, C&E diagrams or Fishbone diagrams)
- Pareto charts or Pareto diagrams
- 5 Why’s
- 5W and 2H (Who, What, Where, When, Why, How, How often)
- Statistical Process Control (SPC)
- Scatter plots or scatter diagrams
- Design of Experiments (DOE)
- Check sheets
- Histograms or Capability Analysis
- Failure Modes and Effects Analysis (FMEA)
- Flowcharts or Process Maps
Learn more about 8D:
- 8D on Wikipedia
- Ford 8D Overview (2002)
- Take a root cause analysis course (which covers 8D and root cause analysis tools): Live classroom or Online