Concealed Carry Question

Greetings!

I am in the process of deciding whether to independently go to a school or go the company-training route. I have finally decided to make the career switch after some long hard thinking. I'm wondering if there is an industry standard (or law) regarding the carrying of a concealed weapon while on the job? Is this a company-by-company rule, or does one size fit all? Is it possible/legal/ok with carriers to carry while on the job? I can easily see some inital problems, ie state by state laws differing, etc. I'm just wondering if anyone has any experience with this topic?

I have many more unrelated but specific questions about the career, but I will save those for the proper forums.

Thanks,
Boogdaddy