A Welder's Qualification Lapses Mid-Contract
A pressure-vessel shop has twelve welders on a six-month contract. Welder A qualified in month one on the production procedure and has welded continuously since, but his qualification certificate carries a expiry date that fell three weeks ago. Nobody noticed because the welder's continuity record shows uninterrupted work on the same procedure. The welding coordinator has been on leave and the deputy signed the last four weeks of inspection reports without checking dates. Thirty-one vessels have been welded in the affected period, fourteen already dispatched. The client's surveillance visit is in two days and will sample welder documentation.
1. Distinguish continuity of work from validity of qualification, and say whether the welder was qualified during the affected period.
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Continuity and validity are different controls. Continuity answers the question 'has this welder used the procedure recently enough that skill is not stale?' Validity answers 'is there a current instrument attesting the welder's competence?' A welder can satisfy the first and fail the second.
On the facts, the qualification certificate expired three weeks ago. Unless the applicable scheme provides for automatic extension on continuous work, or the certificate was renewed before expiry, the welder was not qualified for those three weeks, whatever the continuity record shows. The continuity record is evidence supporting renewal; it does not renew anything by itself.
The coordinator should state this plainly rather than argue the point: the welder was unqualified from the expiry date, the fourteen dispatched vessels were welded partly in that window, and the position must be disclosed to the client before the surveillance visit rather than discovered during it.
2. The coordinator must decide what to do about the thirty-one vessels, fourteen of them already with the client. Set out the decision framework.
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The framework turns on what the qualification actually assures, and on what evidence exists independently of it.
Step one: establish which welds fall inside the unqualified window. Weld dates, not vessel completion dates, determine exposure.
Step two: ask whether the welder's competence is in fact in doubt. He qualified on this procedure, welded it continuously, and there is no reported defect trend. That supports a judgement that risk is low, but it does not restore the paperwork.
Step three: choose proportionate verification. Options run from review of existing inspection and NDT records for the affected welds, through targeted re-examination (surface and volumetric) of a sample, to full re-test of the welds. The choice should be justified by service condition, joint type, and the defect history.
Step four: for the fourteen dispatched vessels, notify the client with the facts and the proposed verification; do not wait for them to find it.
Step five: renew the welder's qualification immediately, and record the corrective action. The decision must be documented with reasons, because the coordinator is accountable for it whether or not a defect is found.
3. The deputy signed four weeks of inspection reports without checking welder dates. What does this reveal about the quality system, and what single change would most reduce recurrence?
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It reveals a control that depends on one person's memory rather than on the system. The deputy was signing as a competent person but had no checklist forcing a date check, no register showing expiry dates at a glance, and no rule that a signature is invalid without verification of the welder's current status. The coordinator's leave exposed the gap; it did not create it.
The most effective single change is a welder qualification register with forward expiry dates and a look-ahead alert, reviewed at a fixed interval, so that expiry is visible before it happens rather than discovered afterwards. Coupled with it, a signature block on the inspection report that requires the welder's qualification reference and expiry date to be entered, making the check unavoidable at the point of signing.
Training the deputy is useful but insufficient: the same failure will recur with the next deputy, or the next leave. The system change is what converts an individual lapse into a controlled process.