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Digitally Signed and Sealed Drawings

I just received a sealed structural plan. It has a seal, date and signature in ink, all either scanned or flattened. It also has a "digital signature" space next to it, and when I click on it, I can digitally sign it. I just don't understand!
I don't know what to tell you. If they are scanned, it is obvious and we don't accept them. What do you mean by flattened?
 
There is a difference between digitally signed document and an electronically signed document.

A digitally signed file can provide proof that that the contents of the file have not changed since it was digitally signed. It can also provide a link to the entity that applied the digital signature so you can establish who applied the digital signature. A digitally signed file does not need to include a graphical representation of a signature although state licensing laws might require a graphical representation of a stamp and signature.

A paper document cannot be digitally signed even though the file used to produce the paper document is digitally signed. It is the file that is digitally signed.

When talking about electronic signatures California defines the terms different from Colorado.

In California an electronic signature does not have the ability for self-authentication of a digitally signed document and can consist of a scanned image of a signature. California law also has provisions for digital signatures, but this is not required by the licensing board. While this is legal this is much less secure and there have been instances where an individual has inappropriately inserted a scanned image of a stamp and signature in a CAD file that was not produced under the control of the engineer's name on the stamp.

The ultimate concern is did the individual intend to take responsibility for the document. A wet signature on paper or a digitally signed document are considered self-authenticating and it is assumed no other proof is needed. In the absence of a self-authenticating signature responsibility can be established if there is supplemental evidence that the individual intended to take responsibility. Thus, a scanned image of the stamp and signature may be legally valid even if the file was not digitally encrypted.

Some jurisdictions in California have a policy preventing the electronic submission of a digitally encrypted file. Their argument is that if the file is encrypted, they cannot apply their stamps to the electronic file. This is a problem both because it denies the design professional to protect his file and because, while not normal, there have been instances where the building department personnel have made changes to the file that the design professional did not agree to. The building departments need to find a solution that allows engineers and architects to digitally encrypt their files.

As noted previously, in California the building department does not have the legal duty to verify that the document was digitally signed. There is a difference between building code law which governs the building and professional licensing law which regulates the architects and engineers. Just as the state licensing boards do not have the authority to enforce the building code the building departments do not have the authority to enforce licensing laws.
 
I don't know what to tell you. If they are scanned, it is obvious and we don't accept them. What do you mean by flattened?
Flattening a document protects the mark-ups so they can't be altered. I apply a watermark to every page, then flatten all my mark-ups, stamps and watermarks, and finally secure the document with a password before I send it back out. BTW, we "require" documents to be flattened before they are sent to us. Some do, some don't. When they don't, I am able to lift/alter their data, including seals. I copied and pasted one from one plan to another to prove my point when I started here to demonstrate how important document security is. To date only one other person does it here, so the AHJ is as guilty as the DP's who submit.

BTW...Congratulations on BO of the year. Saw it on Linkedin.
 
Following are two excerpts from the state board. I have a plan in front of me, a pdf reviewed with BB. It has a seal, with a date and signature across the seal. So I wonder how it has come to be. Was it a paper plan, which has been scanned? (That seems unlikely) If the plan is "computer generated" (likely), was the stamp also computer generated? Is a pasted image considered "computer generated? What does "computer generated" mean? (the same rules apply to architects)
The stamp on the electronic version that you show is meaningless. What is visible on the drawing for signature and sealing purposes is not relevant. What is inside the file, where it is verified as digitally signed and sealed is what counts. An Adobe signature, for example is meaningless in Florida.
 
Just did an inspection for some small changes is a tenant fit-out job. The sealed electrical plans looked like it was copies form a previous fit-out job with some lighting and receptacles added. When I did the inspection, I could not tell the deference between the existing and new ones on the plans. The architect told the owner to just mark the new ones himself on the sealed plans.
 
Just did an inspection for some small changes is a tenant fit-out job. The sealed electrical plans looked like it was copies form a previous fit-out job with some lighting and receptacles added. When I did the inspection, I could not tell the deference between the existing and new ones on the plans. The architect told the owner to just mark the new ones himself on the sealed plans.
Then part of your report should be that the work is not per the approved plans, and you will need as-builts for the final inspection.
 
I don't know what to tell you. If they are scanned, it is obvious and we don't accept them. What do you mean by flattened?
Many image-management systems work in "layers," where different parts of the document are in different sub-files, overlain on each other. The final image is the totality of the layers, with the top layers obscuring whatever may be beneath (unless they are set to a transparency). In your typical off-the-shelf magazine, the model's head might well be on the top layer, cutting off a part of the magazine title below, for example. If you looked the raw file for that cover, it might have several different layers. But a "flattened" image would have just one set of image info, much like what would come off a camera, for example.

Used to work in layers in Photoshop all the time.
 
Many image-management systems work in "layers," where different parts of the document are in different sub-files, overlain on each other. The final image is the totality of the layers, with the top layers obscuring whatever may be beneath (unless they are set to a transparency). In your typical off-the-shelf magazine, the model's head might well be on the top layer, cutting off a part of the magazine title below, for example. If you looked the raw file for that cover, it might have several different layers. But a "flattened" image would have just one set of image info, much like what would come off a camera, for example.

Used to work in layers in Photoshop all the time.
This was covered in another reply. I was questioning the context of his use of the word flattened. I am more than familiar with flattening in Photoshop and in the context of PDF files.
 
We are fighting this battle now. The state laws governing architecture and engineering have included specific requirements for digital seals and signatures for many years, but what we usually see is just PDFs with what is obviously just a JPEG scanned image of a seal and signature. That doesn't cut it. The law requires third-part authentication. Our state building inspector recently sent a notice to all building officials that we have to start checking this.

The major PDF readers have long had provision to do this. If I open a document with a proper digital seal in Adobe Reader, Adobe Acrobat, Bluebeam Vu or Bluebeam Revu, the software pops up a notice that tells me the document was digitally signed -- and whether or not the digital signature is valid. If Adobe doesn't pop up this colored band across the top -- any seal and sinature are nothing but a scanned image of a seal and signature, which is NOT a proper digital seal.

Here's a sample in Adobe Reader: (note that this was submitted several years ago. The digital signature was valid when it was submitted, but the engineer's authentication key has changed since then):

1705355189762.png
 
I should add that we don't have to understand what "flattening" is or how it works. The laws (at least in my state) require digital seals and signatures on electronic submittals, and the laws spell out that this means third-party authentication. How the design professional accomplishes this isn't my problem. The laws have been on the books literally for decades. The larger A/E firms seems to have figured out how to do it. If the smaller guys want to stay in business in the digital era, they're going to have to learn how to do it, too.

We recently rejected a set of drawings from our arch-nemesis, a PE civil engineer in town who likes to play architect. His digital drawings have seals that don't pop up the recognition of a digital seal, so it's obvious that he just scanned a seal and signature and pastes it into each sheet. When we flagged it, his excuse was that he is aware of the law but that he doesn't do it "out of concern for security." Which is a crock, because anyone can copy his JPEG seal and signature image and reproduce it, but nobody can copy a proper digital seal and signature. So what he really means is that either he doesn't have a clue how to do it, or he's too cheap to pay a third-part authentication service.

Bottom line (for us) is that if we open the PDF and we don't see the notice that it's a valid digital signature -- the documents aren't acceptable.

A proper digital signature will either change or disappear if the document is changed after it has been signed.
 
How do you verify a wet signature?

My sense is that in most states that the building department does not have a legal duty to verify the validity of signatures.

I'm coming to this discussion late, as a result of a link from a more recent discussion.

Our state building inspector recently reminded us that we DO have a duty and responsibility to verify seals and signatures, and to verify that digital seals/signatures are third-party authenticated digital seals/signatures, not just JPEG scans of a seal and signature.
 
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