Not to split hairs, but it is important to understand that UL does NOT test "performance.' Their tests are strictly focused upon, as their motto used to say, "testing for public safety." There is NO requirement that the product work - let alone work well. (This would become all too clear if it were easier to actually obtain, and read, one of their standards !!!)
Nor, in many cases, are the standards 'their' standards. Even when UL was the 'author,' often thay have given up control of the standard by having it ANSI or ASTM adopted. In addition, they make great efforts to have their standards conform to codes and stndards developed by completely separate bodies.
I do not say this to "disrespect" UL, nor do I say UL is the "cats' meow." Their input - as in the dispute over 'classified' breakers - is often valuable. Nor, ultimately, does this discussion have anything to do with UL.
I cannot stress this enough: The AHJ is the AHJ! That is, the responsibility is on HIS shoulders, and his alone. The presence of UL sticker, or a quote from a code book, are only tools he can use to help him make his decisions. Far too often folks take the lazy way out, and blame UL for the decisions THEY must make.
Ultimately, there may be a difference of opinion between the government (the AHJ) and the governed (us). Again, the listing information and code books are but tools we use to identify the issues. Then we both get our shot at persuading a dozen strangers as to our view ... but that's going a bit beyond this topic.
