One Engineer Stamps Calculations another Engineer Stamps Drawings

[JKJohn]

Hi all -
I am reviewing engineering drawings. The firm has provided calculations stamped by one of their engineers and drawings stamped by another engineer. Not that it matters, but both engineers work for the same firm.

Is there an issue with this?

Thanks in Advanced!
John

 

[JStephen]

I would say generally not, with some variation depending on the circumstances.

 

[JAE]

I don't think this is appropriate in most USA states. There should be one (1) engineer of record per discipline per each entity.
The only thing would be if the calculations were developed and the original EOR left the firm, then the second EOR reviewed (thoroughly) all the calcs and then completed the plans.

 

[fel3]

JAE…

I agree that the same PE should stamp and sign both his/her drawings and the calculations that support them for the reason you cite....most of the time. I say "most of the time" because I have worked on projects (including a couple recent ones) where it made more sense to have one engineer stamp and sign the calculations and have another engineer stamp and sign the drawings.

In the past, when I managed my own projects, and often did the bulk of the design, I always stamped my drawings and the calculations that supported them. My current role now consists mostly of performing QA/QC reviews, training, mentoring, technical assistance, business development, etc. But, from time-to-time, I am asked to perform calculations that the design team (including the EOR) doesn't have the expertise to perform and there isn't time in the schedule for me to train someone.

For example, in 2018 I performed a multi-scenario steady-state hydraulic analysis for a stick (i.e., non-looped) piping system for a large, multi-discipline project, working in close coordination with the pipeline EOR. He has a lot of pipeline design experience, but had only ever performed relatively simple hydraulic calculations using a calculator or Excel. He had never modeled a system this size using dedicated network analysis software. (To me, the system was small, but it was beyond his current ability. In fact, he had tried to model it in Excel and 80+ man-hours later had buried himself in a confused mess. I joined the company as he was attempting to complete and debug his model. I suggested letting me build an EPANET model, and in less than a day I had it up and running. We have known each other for years and he was glad to hand it off.) As soon as we had iterated the pipeline design and the steady state analysis to a reasonable solution, we passed my model along to another engineer to run a transient analysis. My previous experience with transient analysis was limited to simple calculations, so we needed a third engineer to do that analysis. I had already performed some simple transient calcs to verify pipe pressure classes, but we needed a complete transient model using dedicated software, especially to identify low pressure waves. In a case like this, the hydraulic calculations informed pipe sizes, pipe pressure classes, air/vacuum valve sizes and locations, etc., but had no direct effect on the detailed pipeline design and the plan and profile presentation in the drawings. So, one pipeline EOR and two other expert PEs to back up the design, with us each stamping and signing our parts.

And, on the same project, I performed some structural calcs for well casings (axial tension, axial compression, collapse strength, and burst strength). The well design EOR has decades of well design experience, but none whatsoever for well casing calcs. In the past, he had used "cheat sheet" tables for preliminary design, then delegated the final design to the contractor's casing vendor. But, our contract required us to submit the four calcs I just listed as part of our final design package. He was very happy to learn that I already knew how to do these calcs. My calcs didn't affect the design (the casing thicknesses from the "cheat sheet" tables were good), they just proved it worked. So, one well design EOR and my PE to back up the design.

============
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[JStephen]

Let me expand on my answer a bit.

For one engineer on the calcs and another one on the drawings, it assumes that both of them are fully familiar with the project, and that one or both is coordinating their end of it to the other person's work. If that's not the case, you have a problem, but the problem isn't two different seals, and putting one person's seal on both won't fix that problem, either. The two-seal situation can come up in normal work flow, or could be the situation with one engineer dying, leaving, or just being on vacation.

As noted above, the common practice is to have one seal per discipline. On the other hand, on any very involved project, you're bound to have more than one PE per discipline generating the material, and for one person to seal 300 pages of drawings almost certainly means they are sealing a bunch of stuff they've hardly had a chance to glance at. So you're about as apt to generate ethical issues trying to shoehorn everything under one seal as you are in using different seals on different parts of the work.

A similar issue might come up with sealing drawings and specifications for a project. We've bid on a few jobs where it was pretty obvious that the person writing the specs had never even said "hello" to the person doing the drawings, whether it was one seal or many.

 

[phamENG]

I'd be concerned if it's either a small project or a even a large but "self contained" project. Ideally speaking, the drawings are based on the calculations. Without calculations, you don't have an engineered design shown on your drawings. So I would absolutely expect them to be sealed by the same engineer. If they aren't, I would want an explanation - a letter from the engineer sealing the drawings stating that the original engineer had retired (or whatever happened), but they had fully reviewed and confirmed the original calculations and accepted the necessary liability for their use.

That said, in a more complex project multiple seals are ok. Take a PEMB, for example. The superstructure is sealed by one engineer, and the foundation by another. Scaling it up a bit, say you have two semi-independent high rises on a common 6-story parking garage podium. Engineer 1 designs high rise 1 (calcs and drawings), engineer 2 designs high rise 2 (calcs and drawings), and engineer 3 uses inputs from 1&2's calcs to design the base. In all instances, however, the drawings and calcs are sealed by the same person - but the project is broken up a bit.

Be careful, though - some jurisdictions may have tighter rules on what it means to be the EOR. In most cases, there can be only one...