One item fails in an otherwise acceptable sample. Does the whole lot have to be rejected?

Neither outcome follows from the count alone. Identify the failed requirement and apply the agreed sampling decision rule. Keep the failed piece out of released stock while the quality authority decides the lot status. Replacing that piece does not, by itself, resolve the original sample result.

Identify the characteristic, failure and agreed decision rule

Record what failed, the observed result, its acceptance limit and the method used. Check the part identity and drawing revision before classifying the finding. A damaged label, an out-of-limit dimension and missing required evidence are different findings; do not combine them into an unexplained total of “one defect.”

Locate the inspection plan that applied when the sample was chosen. It should identify the relevant population and the decision path. If the order has no agreed rule for this case, escalate the gap rather than borrowing a threshold from a different purchase. The receiving-inspection guide is useful background, but it cannot supply a missing order-specific decision rule.

Separate the failed piece's status from lot disposition

Assign a clear status to the individual failed piece and a separate status to the lot. A nonconforming piece can be held while the lot decision remains open. Equally, an acceptable lot decision under an approved plan does not turn a known failed item into a conforming one.

Preserve the original selection list, all passing results and the failure evidence. Note whether the finding could affect related stock, such as pieces sharing a material or process reference, without declaring a common cause that has not been investigated. Ask the responsible reviewer whether containment needs to extend beyond the sampled piece.

If the reported failure is disputed, remeasurement should address that dispute under a documented method. It should not become an unrecorded search for a passing value. Keep the original and revised findings linked, including the reason any result was corrected.

Follow the approved sampling plan or authorized escalation rather than inventing a rejection threshold

Follow the authorized next step: lot disposition, further sampling where the plan permits it, screening, rework or technical investigation. Do not add a handful of new samples simply to dilute the original failure. Where a second stage is part of the plan, document that stage and its decision rule before drawing conclusions.

For the carbide blade batch, ask the supplier to acknowledge both the failed-item status and the lot decision. This prevents a replacement shipment from being treated as closure of a wider unresolved issue. Record any proposed remedy separately from the technical acceptance decision.

The final record should explain why the lot was accepted, rejected or held and what happened to the failed piece. If the agreed process does not settle the case, name the person authorized to decide it. The goal is an accountable disposition, not an automatic rejection policy or a casual exemption for a small failure count.