Just got my Luna BBS02 kit and bottle battery in today! Can't wait to start installation!

I got the Luna 52V smart charger, and in the little manual it says to not charge the battery in a house, and preferably charge it inside a BBQ grill or "lipo safety bag". Really? I assume they mean put the battery itself into the grill or bag in case of fire, but the charger should be outside for cooling and air flow, right? That seems kind of crazy. I don't think I want my battery sitting outside, especially with it being quite cold this week. What are others doing for charging, and charging safety?