I would like to bring my 10 year old son to a 16+ show. I’ve seen other Q&A’s here re: the underage thing but not re: what the lowest permissible age was. Is it possible to get him in and would I need to bring a copy of his birth certificate?

On the website they state that you can enter a 16+ show if you are 10+ with a guardian unless otherwise specified.

I dunno about the Ogden, but I know I've seen very young kids at shows with their parents at other venues in Colorado, so there must not be a legal restriction of note. I agree that you should probably conform that with the head of security before you buy/go.

I believe the 16+ limit is for children *without* a guardian.

You should be ok just ask to speak to head of security