if any fire is contained in anything then, by deffinition, it aint open, is it? BBQ's start by lighting wood / charcoal, initially with fire. Only after 20 min or so can you begin to BBQ food, on the embers. I have done many times, rekindle the bbq after the food was cooked and had a small "contained" fire in the tray, just enough to keep warm on those cooler nights. Never had anyone ever whinge about it. Then again, maybe Iv'e just been lucky?