SEIT:
There isn’t technical literature on every detail and every situation, so you can’t count on that in every case. You might explain the problem here in detail and get some outside ideas or direction. Maybe someone outside your office has run into this issue before. But, you do have a gut feeling that you should get resolved. You seem smart enough to me too, so that I would give you a listen if you came to me with your concerns. And, I would try to explain to your satisfaction, but you better come with evidence, because I know that what we have been doing has worked in the past. We all hate to admit that we were wrong or could do it better, all at the hands of the young guy.
I agree with TXS when he says that the boss is signing the plans and has ultimate responsibility. You usually do have trouble arguing with success, when it has worked before. But, most good bosses will explain their thinking when asked properly, and presented with sound, logical well reasoned concern, given a little time so cooler heads prevail. We want you to succeed, you’re the best asset we’ve got, we secretly want you to keep us on our toes, we’re not infallible. Approach each of the ‘others’ individually to air and explain your concerns. Sometimes you get a better hearing, one-on-one, when the group thinking thing, agree with the boss mentality isn’t prevailing.
I agree with Ron, but would say it a bit differently. You must present your best case, explaining your concerns, with whatever corroborating evidence you can find. Explain your gut feeling with the best evidence you can muster, and dissect what they are doing with your best examples and disproofs at every step along the way as to why you think their way is unsafe or wrong. I don’t think Ron meant notarized letter, by certified mail.
Good Luck