8D Problem Solving contains immediate impact while parallel analysis identifies deeper causes. Verification shows whether the selected correction actually resolves the problem.

1. 1

   D1 Team

   Mandated team

   

   Goal

   Mandated team: Appoint a small cross-functional team with process knowledge, authority, lead, and sponsor.

   Inputs for this step

   • Confirm problem significance, initiate immediate protection, and secure sponsor plus cross-functional expertise for 8D.
   • 8D report, 5W2H problem statement, containment log, occurrence and escape-point evidence, correction and prevention plan

   Actions

   • Appoint a small cross-functional team with process knowledge, authority, lead, and sponsor.

   Output

   Mandated team

   Appoint a small cross-functional team with process knowledge, authority, lead, and sponsor.

   Quality check

   Does the team cover occurrence, detection, and customer impact?

   Pitfall

   Quality works alone without process authority. Add missing occurrence, detection, and decision roles.

   Timing: 30–60 minutes

2. 2

   D2 Problem

   5W2H statement

   

   Goal

   5W2H statement: Quantify the problem with 5W2H and document Is/Is-Not boundaries.

   Inputs for this step

   • Mandated team

   Actions

   • Quantify the problem with 5W2H and document Is/Is-Not boundaries.

   Output

   Problem statement

   Quantify the problem with 5W2H and document Is/Is-Not boundaries.

   Quality check

   Are who, what, where, when, relevance, how, and how many described without causal claim?

   Pitfall

   Faulty batch is fixed as the problem statement. State observation and boundary; leave causes open for D4.

   Timing: 45–90 minutes

3. 3

   D3 Contain

   Effective containment

   

   Goal

   Effective containment: Choose interim containment actions to protect customers; monitor effectiveness and side risk.

   Inputs for this step

   • 5W2H statement

   Actions

   • Choose interim containment actions to protect customers; monitor effectiveness and side risk.

   Output

   Containment

   Choose interim containment actions to protect customers; monitor effectiveness and side risk.

   Quality check

   Does it protect immediately without pretending to be permanent correction?

   Pitfall

   Restart is treated as permanent and not monitored. Record ICA target, owner, measure, expiry, and removal condition.

   Timing: Immediate until cause confirmed

4. 4

   D4 Causes

   Verified causes

   

   Goal

   Verified causes: Identify occurrence cause and escape point and verify both through data or reproduction.

   Inputs for this step

   • Effective containment

   Actions

   • Identify occurrence cause and escape point and verify both through data or reproduction.

   Output

   Cause evidence

   Identify occurrence cause and escape point and verify both through data or reproduction.

   Quality check

   Are both occurrence and non-detection proven?

   Pitfall

   The most plausible fishbone idea is selected without testing. Test every candidate against data, reproduction, and counterexample.

   Timing: One to five days

5. 5

   D5 Correction

   Verified correction

   

   Goal

   Verified correction: Select permanent corrections and quantitatively verify cause removal, risk, and customer requirement before release.

   Inputs for this step

   • Verified causes

   Actions

   • Select permanent corrections and quantitatively verify cause removal, risk, and customer requirement before release.

   Output

   Tested correction

   Select permanent corrections and quantitatively verify cause removal, risk, and customer requirement before release.

   Quality check

   Does the correction remove the cause without unacceptable side effects?

   Pitfall

   The largest solution wins without verification. Pilot options against the cause and guardrails before approval.

   Timing: One to three days

6. 6

   D6 Implement

   Validated implementation

   

   Goal

   Validated implementation: Roll out permanent correction, validate it, and withdraw containment in a controlled way.

   Inputs for this step

   • Verified correction

   Actions

   • Roll out permanent correction, validate it, and withdraw containment in a controlled way.

   Output

   Effect evidence

   Roll out permanent correction, validate it, and withdraw containment in a controlled way.

   Quality check

   Does effect persist in operation, with containment removed only afterwards?

   Pitfall

   Containment ends at deployment rather than after evidence. Set validation window and removal criterion before rollout.

   Timing: One to four weeks

7. 7

   D7 Prevent

   System prevention

   

   Goal

   System prevention: Update similar processes, standards, FMEA, tests, and controls to prevent recurrence elsewhere.

   Inputs for this step

   • Validated implementation

   Actions

   • Update similar processes, standards, FMEA, tests, and controls to prevent recurrence elsewhere.

   Output

   Prevention plan

   Update similar processes, standards, FMEA, tests, and controls to prevent recurrence elsewhere.

   Quality check

   Were similar systems and the management-system gap examined?

   Pitfall

   Only the affected service is patched. Extend shared cause and escape control to similar products and processes.

   Timing: One to three weeks

8. 8

   D8 Recognise

   Closed 8D

   

   Goal

   Closed 8D: Close result, learning, and team contribution formally; approve report and hand over long-term controls.

   Inputs for this step

   • System prevention

   Actions

   • Close result, learning, and team contribution formally; approve report and hand over long-term controls.

   Output

   8D closure

   Close result, learning, and team contribution formally; approve report and hand over long-term controls.

   Quality check

   Are customer impact, effectiveness, residual actions, and team contribution transparently closed?

   Pitfall

   Case closes without handover once failures disappear. Record approval, residual controls, communication, and recognition.

   Timing: 30–60 minutes