A welding supervisor in a CSA W47.1 certified shop observes a welder using a filler metal that is not listed on the approved Welding Procedure Specification (WPS) for a specific job. The welder states that the filler metal is 'similar' to the one specified and will produce acceptable results. What is the most appropriate action the supervisor must take according to CSA W47.1 guidelines?

Question: A welding supervisor in a CSA W47.1 certified shop observes a welder using a filler metal that is not listed on the approved Welding Procedure Specification (WPS) for a specific job. The welder states that the filler metal is 'similar' to the one specified and will produce acceptable results. What is the most appropriate action the supervisor must take according to CSA W47.1 guidelines?

Answer options:

• Allow the welder to continue, but monitor the weld quality closely. ✅ Immediately stop the welding operation and ensure the correct filler metal is used or a new WPS is qualified.
• Document the deviation and seek post-welding engineering approval.
• Conduct a small test weld with the 'similar' filler metal to verify its suitability.

Correct answer: Immediately stop the welding operation and ensure the correct filler metal is used or a new WPS is qualified.

Explanation: CSA W47.1 requires that all welding be performed in accordance with a CWB-approved WPS. Using an unapproved filler metal, even if seemingly similar, constitutes a deviation from the qualified procedure. The supervisor must halt the operation to ensure compliance, either by using the specified filler metal or qualifying a new WPS. Deviating from the WPS without approval jeopardizes the integrity of the weld and the company's certification.