Need help with Glass and UV Radiation Protection

[spllbnd2]

Okay so I am looking to get some custom cut glass for a DE 150 bulb. But when I asked one glass company about the types of glass they offer, I was told the following,

"Alex:

High temperature ceramic (Neoceram or Pyroceram)
both are excellent at passing UV. They tend to
restrict IR. Temperature are good for a
continuous temperature in the 1400 deg F range.

Tempered glass is good up to about 400 deg F or
so. UV can be reduced somewhat be select a darker
tint."

So then I do more research to find that of the three types of UV rays,
UVA, UVB and UVC, that standard glass is only going to block UVB rays, which is the UV that causes sunburns and skin cancer. And further more, glass does not block UVA rays. UVC rays are absorbed by the ozone layer and do not reach the earth's surface.

So with all this reading I am now throughly confused. Questions are,
* What type of glass does a DE bulb need?
* What actual UV rays does a metal halide DE bulb emit? UVA? UVB? UVC?
* Does normal tempered glass / standard glass work enough for the aquariums and corals, even though it will only block out the UVB rays?

So confusing

Thanks for the help and any advise.
Alex

 

[spllbnd2]

Okay after yet further research I've found the following information in regards to UV rays.

Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm. And from what I've found, the UV from the 315 nm and above is the least harmful of the UV rays, but can still cause DNA damage. So question then remains,

*Do the UV rays above 315 nm affect the corals in the aquarium? Considering with standard glass we are only able to block 10% of the UV rays above 315 nm?

UVC = 100–280nm: Most harmful and used in sterilization to kill biological organisms.
UVB = 280–315nm: Harmful and causes sunburn, skin cancer, and eye damage.
UVA = 315–400nm: Longer wavelength and less energy than other UV. It is the least harmful but still can be damaging to DNA and the human eye.

 

[Krish]

I have no idea how all that works! If possible, maybe you should see if you can find out what the se bulbs are made out of (the glass) as those bulbs don't need anything under them as the bulb's shield/glass itself protects the tank from the uv rays. That way, you will know what type of glass to look for. Just a thought in the meantime as you wait for more responses.

 

[spllbnd2]

Thanks for the idea Krish. Hope you're feeling better.

I assume the SE bulbs may have more silica in the glass that covers them as well as some sort of UV coating maybe. Don't really know yet. I do know that I have a 70 watt DE in a DIY pendant with tempered glass and It seems to be okay.

 

[thatguy559]

just get the glass that has uv protection in it....i know when i ran my plasma with out the glass i sun burt all my corals most made it i did loose a blue acro it went from blue to pink in one day then slowly died. all i did was go to a glass shop and aske for a picture glass that has the uv block in it so it doesnt fade the picture. works like a champ

 

[Krish]

Thanks for the idea Krish. Hope you're feeling better.

I assume the SE bulbs may have more silica in the glass that covers them as well as some sort of UV coating maybe. Don't really know yet. I do know that I have a 70 watt DE in a DIY pendant with tempered glass and It seems to be okay.

Thanks Alex! You know if Don is around (DonW), he'd probably have a pretty good idea. Hopefully he sees the thread and chimes in. Pretty smart fellow lol!

 

[spllbnd2]

just get the glass that has uv protection in it....i know when i ran my plasma with out the glass i sun burt all my corals most made it i did loose a blue acro it went from blue to pink in one day then slowly died. all i did was go to a glass shop and aske for a picture glass that has the uv block in it so it doesnt fade the picture. works like a champ

Yes. I have thought of ordering picture frame glass with the UV coating. But I still need to make sure that I can get this tempered as well.

Thanks for the advise. What glass shop did you get your glass from?

Cheers,
Alex

 

[thatguy559]

right here in oak harbor....you dont need tempered mine is not tempered