House of Blues Chicago dress code?

I'm going to see Ministry at House of Blues on Friday with some friends and my boyfriend. My bf wants to wear his German Kevlar vest and a German Dragen Gasmask (w/o the canister). I am wondering if they have anything in their dress code policy that prohibits either of these things. I know in some other places, they let him wear the gasmask as long as it didn't have the canister attached, but having never been to this particular House of Blues, I'm not sure if they have the same policy. I think the vest will be fine, but the gasmask makes me wonder. I looked on their website and it said nothing about dresscode. Anybody familar with this that can help me?