The Stamped Drawing That Outlived Its Assumptions
You are a certified engineering technologist at a 40-person firm. In March you sealed a structural bracket design for a client's conveyor upgrade, based on a stated service load of 12 kN and an ambient temperature of 20 °C. In September the client's maintenance supervisor emails you directly: they have doubled throughput, the bracket now sees roughly 24 kN, and the motor housing nearby runs at 70 °C. He asks you to "just confirm it's still fine" by reply email so he can sign off on the expansion, and says the project manager told him you would not charge for a quick look. Your seal is on the original drawing, which is now pinned in the plant. You have not been retained for the expansion, and the client has not asked your firm for a new scope or purchase order.
1. What should you do about the request to confirm by email, and why?
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Decline to confirm by email, and say so promptly and in writing. A one-line confirmation from the sealer of the original drawing is a professional opinion on a changed design condition, and it will be read by the client as an endorsement of the expansion. The original seal was issued against a 12 kN service load at 20 °C; at 24 kN the load has doubled, and at 70 °C the allowable material properties and any thermal expansion assumptions may no longer hold. Neither condition is within the basis of the sealed design.
The correct path is to explain the basis of the original seal, state plainly that the new conditions fall outside it, and offer to perform a re-evaluation as a properly scoped engagement through your firm. Copy the project manager so the commercial side is aligned rather than left to a verbal promise. Do not let the "no charge for a quick look" remark pull you into giving an unpaid informal opinion on a safety-relevant change. The seal is a claim about specific conditions, not a general warranty that the hardware is adequate forever.
2. The client ignores your reply and proceeds with the expansion, leaving your sealed drawing in place. What are your obligations now?
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You have a duty to act on the risk, not merely to have warned once. Because your seal remains on a drawing that no longer matches the installed service conditions, a reasonable observer could attribute the adequacy of the modified system to you. Steps to take: (1) send a written notice to the client and your project manager stating that the sealed design is valid only for 12 kN at 20 °C and that operation outside those limits is outside your professional scope; (2) recommend the drawing be marked superseded or that a prominent limitation note be added to the plant copy; (3) document the dates and content of all communications; (4) consult your firm's principal or quality manager about whether to notify the client's engineering lead or, if there is an imminent risk to workers, the appropriate authority.
If you believe the modified installation presents a danger to life safety, confidentiality does not override the public interest. Escalate internally first, then to the client's senior engineering contact, and only then consider external disclosure, keeping the disclosure narrow and factual. Do not simply withdraw silently: silence while your seal stays on the drawing is the worst option.
3. How should the fee question be handled, given the project manager's verbal assurance?
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Separate the professional question from the fee question, and resolve the fee in writing before doing the work. A verbal assurance by a project manager does not create a scope, and free work on a safety-relevant re-evaluation sets a bad precedent and may not be covered by the firm's professional liability insurance if it is outside the contracted scope. Reply to the client that you are glad to re-evaluate the bracket, that it requires a defined scope (new loads, temperature, fatigue and thermal effects, verification of the connection and supports), and that your firm will issue a short proposal.
Internally, raise the project manager's statement with them and their supervisor. The client was told something the firm did not authorize; that is a commercial and relationship problem to fix, not a reason for you to absorb the work. If the firm chooses to discount or donate the effort, that is the firm's decision, recorded in writing. What you must not do is issue an unpaid verbal opinion that later becomes the basis for the client's sign-off.