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8.1 NCR workflow: detect, quarantine, disposition, close

A Non-Conformance Report (NCR) acts as the immune system of your factory. It flags manufacturing risks—defective parts, process drifts, or documentation errors—and isolates them before they can reach the customer. A weak NCR process can result in “escapes,” where known bad units are accidentally shipped simply because the digital paperwork was closed while the quarantine was breached. This module defines the lifecycle of a non-conformance.

Identification must be immediate and objective. Attempting to introduce subjectivity at the detection stage obscures the true financial scale of quality issues.

The Trigger: Any material, component, or sub-assembly that does not meet the design drawing, the approved BOM, or the designated IPC standard.

The Action:

Whenever a defect is visibly found, tag the physical unit immediately. Avoid setting it aside for later, as memory is an unreliable process control. Whenever the defect yield rate exceeds the formal Shift Trigger (e.g. 3 consecutive station failures), stop the line and notify the lead Quality Engineer.

Mandatory Data Fields:

  1. Part Number & Serial/Lot Number: Traceability is essential.
  2. Defect Code: Use a standardized digital taxonomy (e.g. “Solder Short_U12”, rather than a vague text field saying “Bad Board”).
  3. Physical Evidence: A timestamped microscope photo or raw test measurement CSV attached to the digital record.

Pro-Tip: The status of “Pending Inspection” can be misleading. If a unit is not explicitly stamped “Passed,” treat it as “Failed” until proven otherwise. Always assume unverified material is non-conforming.

The gap between the moment of detection and the moment of physical isolation is where costly escapes typically occur.

Physical Control:

Whenever an NCR is digitally generated, move the suspect unit to the locked Red Box or the designated Quality Cage immediately. For suspect units that are too large to easily move (e.g. loaded SMT Pallets), apply high-visibility Red “STOP” tape around the perimeter and block the system transaction with an ERP Lock.

Digital Control:

Electronically block the suspect serial number in the MES (Manufacturing Execution System). This ensures that even if a board is removed from quarantine, it cannot be scanned or processed at any subsequent station.

Disposition is a technical engineering decision, not a negotiation to meet weekly shipping targets. The authority to decide the final fate of a product scales directly with risk and financial cost.

RoleAuthority ScopeAllowed DispositionsFinancial Limit
Inspector / OperatorDetection Only.N/A (Must Escalate).$0
Quality Engineer (QE)Standard, known Process Issues.Rework (Standard only), Scrap (Low Value), RTV (Return to Vendor).< $500
Quality ManagerHigh Value / Complex Non-Standard.Scrap (High Value), Repair (Non-Standard engineering).< $5,000
MRB (Eng + Quality + Ops)Design / Safety Risk / Customer.UAI (Use As Is), formal Deviation Waiver.> $5,000

Decision Logic:

When the physical fix is clearly defined in an approved Standard Operating Procedure (SOP), the QE can independently approve Standard Rework. When a unit does not meet the print spec but is functionally safe and requires customer approval, the formal MRB must unanimously approve UAI (Use As Is). When the calculated physical recovery labor cost exceeds 50% of the raw unit value, the unit should be Scrapped. Avoid dedicating engineering hours to material that cannot be economically saved.

An NCR is not “closed” simply when the Quality Manager signs the document; it is only closed when the underlying risk to the customer is demonstrably eliminated.

Hard Requirements for Closure:

  1. Execution Verification: The rework was performed correctly, AND the unit successfully passed a complete re-inspection/re-test cycle.
  2. Inventory Adjustment: The scrapped quantities are financially removed from the ERP system.
  3. Root Cause Link: If the NCR was determined to be a systemic process failure, it must be linked to an open CAPA (Corrective and Preventative Action) tracking number.

Pro-Tip: Do not allow “Open” NCRs to age indefinitely. Old NCRs represent stagnant inventory and unresolved systemic risks. Always force a clear disposition decision: fix the issue properly or scrap the unit.

Final Checkout: NCR workflow: detect, quarantine, disposition, close

Section titled “Final Checkout: NCR workflow: detect, quarantine, disposition, close”
Monitored ParameterEngineering Rule / Threshold
Tagging RuleThe Red Tag ID should match the MES Digital Record ID.
Quarantine DisciplineQuality personnel maintain access to the Quarantine Cage.
UAI AuthorityRequires Engineering/MRB sign-off (Never an Inspector or Line Lead).
Scrap AuthorizationMust include a “Scrap Reason Code” for Cost of Quality (CoQ) calculation.
Re-Test RequirementAny Reworked unit must restart testing from the previous passing station.
Closure SpeedDisposition decision typically within 48 hours; Physical closure and unit movement within 5 days.