Chris Lewis wrote:

According to kevin :
... and asking questions of the guy at Home Depot can't hurt a bit.

Um. Do you really... oh nevermind. And while you are at it, you might
as well ask the lady at the hair salon too.

Maybe it's unique to Canada, maybe unique to our local HDs, but the
floor staff at our HD are extremely knowledgeable. The electrical
and plumbing sections each have a list of the professional credentials
of 4 or 5 floor staff (ie: a master plumber with 25+ years of experience),
and at least one is always available.
....

Sounds pretty much of a local "takes your chances" scenario to me...been
in HD's halfway across the US and have yet to find one that has that
level of expertise displayed. Run across a few individuals here or
there that have seemed pretty good, but far more just employees off the
street than anything else. Department managers tend to be reasonably
knowledgable of product, but that doesn't necessarily translate into
trade or regulation expertise.