Quote Originally Posted by oldmac
Hey Dutch,

Recently while looking for a CMH bulb, one of the mfgs (don't remeber which site) was stating they had "new and improved" glass envelope that cut down the amount of radiated UV.

How is that an improvement?
Just b/c the uv might help cannabis it may not all plants, also safety is again a concern if you are in the room under that light while it is on, esp extended periods. If you add uvb separately you can turn it off and enter the room safely with your main lights on instead of during there dark cycle risking letting light in. So it is an improvement to not have your main source of light admitting as much uvb. Hope this helps