I agree,but been running mh in open hoods 20 plus yrs none blown YETheat treated tempered glass ...I agree, if not used remove
unless they are Metal Halides
Mh have a habit of blowing and spraying glass all over
so are needed by most laws and students of common cents
good luck
I have a vented hood and I'm a paranoid about exploding bulbs so I keep the glass clean. I think the biggest dangers are at start up and when spraying anything on the plants.I have air cooled reflectors, but I haven't had a need to duct them, so the glass is just sitting there mounted to reflector, but now I got told by a growshop guy that this glass reduces effectiveness by roughly 20%.
Could there be some truth to what he said?