Where can UL books be purchased? Better yet, is there an online access for viewing UL listings? Right now I'd like to know how many nometalic sheathed cables (Romex) are allowed under standard, plastic Romex staples (surprisingly, the package does not provide this information).
As to the number of cables that can be placed under a single staple you will have to use the information on the package or your own judgment. Most staples, straps, etc. are not UL listed.
If there the regular metal with a plastic insulator than there only good for 1 NM (#14 or #12 AWG. Handy Strap makes all plastic ones with nails and they say right on the box what they are for. These are usually for stacking they come in tan for 2 #14 or #12 grey for 3 #14 or #12 or a 3 wire and white for 10/3 NM etc just look for the listing on the box.
I think UL eliminated distribution of books to inspectors ( which they use to send for free every year) since they went online with the listings. You might get one that is a couple of years old which could still probably serve you well with many things but you'd be taking a chance that a standard was changed--such as the standard for GFCI's.
