Quick question about lighting

I currently have a 400w MH floralux light with like a box design hood, it has a glass plate closing the light within the box. I'm just wondering if it is ok to remove the glass slide and leave the light exposed. I recently did this and it seems a lil brighter to me. I am thinking it may let more UV to get to the plant and whatnot but is this safe and acceptable? thanks,

You only want to use the glass when your lights are vented.

sweet thx