I would double and triple check all of the company's personnel policies. I they haven't given you a current copy since you were hired, ask for one. Companies make changes all the time and don't inform employees of the changes. Then they act all surprised that you woud violate a regulation that you had no idea existed, and when confronted with the intellectual dishonesty of that, they will answer that (paraphrasing) "ignorance of the law is no excuse." If HR asks why you want an updated copy, just tell them that you want to be sure that you have a current copy, that's all. That is a sufficient and rational answer. If HR asks, "do you have any specific concerns?" answer "no, I just wanted to make sure I was up to speed on all of it."
Then, if you still cannot find anything in the policies that would forbid carrying a firearm (or any other kind of weapon, for that matter), then carry to your heart's content, being vigilant that "concealed means
concealed."
RPB, you're on kind of a mistletoe kick this morning, aren't you?

“Hard times create strong men. Strong men create good times. Good times create weak men. And, weak men create hard times.”
― G. Michael Hopf, "Those Who Remain"
#TINVOWOOT