New ANSI Flashlight Standards
I just ran across this article on the Fenixtactical web site. It explains the new ANSI flashlight rating standards.
Here is a article from Inova which gives more information on individual specifications.
Looking them over they are NOT a good indication of the suitability of a light for bicycle headlight use IMO.
The Lumens rating looks good as the way I read it the measured output is what is required to be listed rather than using LED manufacturers ratings. I am in favor of bicycle headlight manufacturers using this standard.
The runtime is the time until output drops to 10% of initial output. IMO this is too low a light output for useful headlight use time.
The beam distance is to the point where beam intensity is .25 Lux. This is about the same as the full moon's light intensity on Earth on a clear night, totally inadequate for a headlight or a flashlight IMO.
Peak beam intensity is listed in Candelas but the original Fenix article does not say at what distance this is specified. The second Inova one states that this can be listed for 2, 10 or 30 meters distance. I wish they had chosen one distance only as the one sample of output listing I have seen did not indicate distance. It looked to me like the maker chose 2 meters probably.
Having a standard, even if not perfect, is a useful step forward and should allow accurate comparisons to be made between flashlights.