Workflow · D3 · The D-steps
D3 — Interim Containment
D3 protects the customer and the business while D4 root-cause analysis is still open. Interim containment is temporary, evidence-based and sized to the suspect population. It does not prove the cause or replace the permanent corrective action.
Key takeaways
- Define lot, date, line, location and customer boundaries before choosing actions.
- Quarantine before sorting, and use a defined capable inspection method where sorting is needed.
- Communicate facts, scope and the next update time rather than premature conclusions.
- Track sort yield, escape checks and customer feedback until exit criteria are met.
Define the suspect population
- Time boundary: from the last known-good point through the last potentially affected shipment or production point.
- Process boundary: line, tool, cavity, shift, operator, material lot or product variant relevant to the evidence.
- Location boundary: plant, warehouse, in transit, distribution and customer stock where applicable.
- Owner and record: identify who is accountable for each containment action and how completion will be evidenced.
Apply interim containment
- Quarantine or hold suspect inventory before disposition.
- Use 100% sorting or additional inspection only with a defined, capable method.
- Add an outbound control when the evidence shows an escape risk.
- Communicate containment status and the next committed update to affected customers or internal stakeholders.
Verify containment and define the exit
- Track sort yield and any defects found after the containment start point.
- Record firewall or outbound-control escapes and customer feedback.
- Review whether the suspect boundary remains adequate as new D2 facts arrive.
- Remove containment only after D6 implementation and validation provide objective evidence that the risk is controlled.
Common mistakes
- Containing only confirmed defects while leaving the wider suspect population unaddressed.
- Calling a sorting activity effective without a defined method or evidence.
- Treating containment as a root-cause conclusion or removing it before validation.
In the Qhubio 8D workspace
How Qhubio structures D3
Qhubio records interim containment as a structured phase with scope, actions, evidence and approval, while keeping root-cause analysis separate in D4.
- Suspect-population and action ownership recorded in the investigation.
- Containment evidence retained with the phase.
- Phase-gated review before root-cause analysis advances.
Frequently asked questions
- Is D3 the same as root cause analysis?
- No. D3 is interim containment. D4 investigates and proves the occurrence and escape causes.
- How quickly should containment start?
- Start as soon as the risk and suspect scope are understood. Customer or company requirements may define specific response timing.
- When can interim containment stop?
- When implementation and validation in D6 provide objective evidence that the permanent corrective action controls the risk.
Related guides
The D-steps
D2 — Problem Description
D2 defines the quality problem with measurable facts: what happened, where and when it occurred, how it was detected, how many units are affected and which evidence supports the description.
The D-steps
D4 — Root Cause Analysis
D4 identifies and proves the root cause and escape cause. Learn how to move from candidate causes to proven root cause in 8D.
The D-steps
D5 — Permanent Corrective Action
D5 selects permanent corrective actions that address the proven occurrence and escape causes, defines ownership and feasibility, and prepares controlled implementation and validation in D6.
Getting started
The 8D steps explained
Walk through each of the 8D steps — D1 team, D2 problem description, D3 interim containment, D4 root cause analysis, D5 corrective action, D6 validation, D7 prevention and D8 closure.
Run this D-step inside a structured workspace
Qhubio is a structured 8D workspace: evidence-grounded phases, phase-gated approvals and audit-ready exports.