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RE: Mechanical Engineer wants me to stamp his M sheets

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Not familiar with your laws. But it would seem equally inappropriate for the ME to stamp and take responsibility for details determined by someone else, if that’s the argument.


However it is your calculations and sketch details which represent the real “evidence-of-suitability” required by regulations. The ME not being able to produce the evidence themselves has relied on a specialist consultant to provide the necessary evidence, just like an architect. The specification of the product and how it is documented and presented is an entirely different matter. The ME as principal designer for the mechanical systems has done the responsible thing obtained the specialist services, and should have no problem declaring the mechanical systems sufficient-for-purpose or compliant with relevant codes: unless thinks employed an SE who is not competent. The ME should be covered if they retain certified copies of your calculations: stamped and sealed if that’s what you do. A certificate or letter uniquely referencing the ME’s documents and the relevant details and a statement indicating that they have been checked for seismic requirements, may also be useful.


It is no different than the architect: the architect as principal designer is responsible for everything concerned with a building project. If the project is simple there may be no structural drawings, but may be a beam by engineer. The architect clearly indicating that sufficiency of such member is determined by an engineer not the architect. The SE doesn’t certify the architect’s drawings unless looked at whole of building, or spends all day writing exclusions. The SE simply provides the requested information in an appropriate manner and the architect incorporates into the main documentation in an appropriate manner.


A complicated electromechanical project could involve mechanical, electrical and structural engineers with all functions integrated in the one detail. But the whole is different than the sum of its parts, and someone has to be the principal designer: one person who has control and authority over the project and can therefore accept responsibility. No doubt the ME will be supervising the installation of mechanical systems, and the SE probably will not be called upon to inspect: it is thus the ME’s domain and they can call the SE if they desire. The contractor certainly won’t be calling the SE directly.


Also from another perspective the ME consultants, could employ another ME on staff who could do the seismic themselves, but only one of the ME’s is responsible for the entire project. Same with SE’s, could have large team of SE’s on a project, but only one is responsible in charge of the whole project. Each individual SE may however have their name as the designer on individual drawings: the principle SE is responsible for accepting or rejecting that done by the other SE’s.


So for document control purposes, the ME can provide some box on the drawings identifying the conditions/functions checked by an SE, and the SE can simply sign: and be provided with copies of the signed documents. Then every time mechanical changes occur, the SE will have to check and sign again. Which is not very practical. The ME is responsible for obtaining SE services if they consider such are necessary, and getting reassessment if they consider mechanical changes have an impact on the scope of work performed by the SE. But otherwise has little to do with the SE, and so little value having their name anywhere on the drawings.


If you didn’t have the licensing, and the stamping and sealing, and were involved with a project that didn’t involve any regulatory approval: what then would be the responsible thing to do? Or if as SE you were principle designer for a project and needed some mechanical input: what action would you take? Given your query, I’d hope you wouldn’t want the ME to stamp and seal your drawings.


(Here in SA we have no licensing: just a requirement for an independent technical check by an independent technical expert, with the regulators permitted to accept a certificate of independent technical expert without question. The important issue is independence: in consequence we reject a lot of stuff from inter-state with licensed engineers who think they are competent enough to self-certify. Only the regulating authority puts any form of stamp and seal on documents.)


Conrad Harrison

B.Tech (mfg & mech), MIIE, gradTIEAust



South Australia