I confess to my ignorance.
A google search came up with the IES, or "Illuminating Engineering Society." I doubt many here are familiar with that group, so some explanation would be helpful.
The IES does have standards LM 79 and LM 80, but both of those seem focused on LED lights. Again, a little background would be helpful.
Otherwise, you'll have to forgive my cynicism. Anyyone who has ever change a light bulb has been bedevilled by bulbs that don't perform as advertised. That's a very large part of the reason you won't find lighting contractors in the aisles of the box stores.
Using the industry's "wunderkind," the CFL, as an example, even the portion that manage to last more than a month don't seem to hold either their brilliance or lighting quality nearly as long as the packaging leads you to expect.
Regardless of whatever test bench results might suggest, it's a bit much to accept that a product that has existed for -maybe- 10 years and is being sold by businesses far younger than that (speaking in general - not a barb aimed at Dayleit) can have anyhting close to a '20 year guarantee.' I can't say where I will be in 20 years, and I doube anyone else can.
So, I'll take the claims of future performance with a very large grain of salt, and see how the products actually perform over time.
