I really don't, it's my first priority. However my second priority is how jealous I am of all the HPS growers out there. Sure my CFLs do everything I expected, and if I could stop following amazing grows I might not have the HPS itch. My cabinet is narrow and I can squeeze a 150 in there but only with inches to spare around the hood, it won't touch but it will be 1.5" away on one side. So my question is.... Will it catch my cabinet on fire?
As a general rule you want a hood at least 12 inches from combustibles like plywood, etc. but that's not set in stone. A lot of people do fine having less space than that.You just have to make sure that after the lamp has been running a number of hours that it isn't heating up the walls or ceiling surrounding the light. Most grow fires are started by faulty wiring. Rarely a bulb will rupture and send molten glass flying in all directions. The most important thing to remember is never let a hot bulb come in contact with water.IMO, it's worth it's weight in gold to spend the extra cash and get a reflector with a glass lens so the potential for a fire started by a rupture is eliminated. Then, run the light on a grounded receptacle, preferably a GFCI. Don't overload circuits and you'll be fine.
Two things you can do . 1) get an air cooled hood (I run 600W bulb with 450cfm Vortex cooling my hood and it is cold to touch) 2) Get Flame defender[ame=http://www.youtube.com/watch?v=STjMZz8gxbA]Sunlight Supply Presents: Flame Defender - Fire Extinguisher for Indoor Growing Environments - YouTube[/ame] P.S.I have 2kg in my 3x3x6 tent .
But obviously cheaper to replace and clean up than to replaced burned down house.... I have one, no problems so far.