Traceability and Lot Control

Traceability links a finished product back to the raw materials, processes, and operators that created it. Lot control groups products made under the same conditions so a quality problem can be contained to a specific lot.

Forward and backward traceability

Direction	Question answered	Use case
Forward traceability	Given batch X of raw material, where did it go?	Recall: identify all products made with suspect material
Backward traceability	Given product serial number Y, what materials and processes were used?	Failure analysis: trace a field failure back to its source

Lot control records

Each lot should record: lot number or date code, raw material cert numbers, equipment IDs and calibration status, operator or shift, process parameters, and inspection results. These records link the product to its production history.

Traceability in regulated industries

Medical devices: UDI (Unique Device Identifier) required by FDA; traceability to implant sites
Aerospace: AS9100 requires traceability to raw material certifications and heat lot numbers
Automotive: IATF 16949 requires lot control and customer-specific traceability requirements

CQE exam tips

Traceability enables targeted recalls — without it, an OEM may have to recall all units, not just affected lots.
Lot size is a risk management decision: smaller lots = more targeted recall but higher overhead.

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