I have to think that one of the most frequently violated codes by Electricians is the often overlooked UBC. I have a lot of examples but I'll stick to just one since it is routinuely violated by almost everyone.
A customer in a commercial business wants a receptacle added so you fish it in for them. We all do this every day, no big deal right? The wall has double layer sheetrock so you need to use madison clips/battleships with the long tines. You install the receptacle, collect the money or get the billing form signed and go on your way. You did a good job right?
WRONG!, you just compromised a two hour fire wall and are in violation of the UBC. The UBC says that boxes in two hour walls must be "firmly" attached to a stud. Please note that you can still use cut-in boxes, but when you cut into the wall it must be against a stud and the box must then be screwed to the stud, and that only metallic boxes can be used.
Also, the UBC states that boxes in two hour walls must be at least 24" center to center. This applies to both sides of the wall in question. The reason for this rule is to ensure that there is only one penetration of one side of the wall in any stud space. Since studs are always either 16" or 24" on center, requireing boxes to be 24" apart ensures that no two boxes will be within the same stud compartment of the wall.
The last time you cut a box into a double layer wall did you fasten it to a stud? Did you look at the other side of the wall first to make sure there weren't any existing boxes within 24" of your cut-in location? Did you add your cut-in alongside an existing data/phone/power box that was within 24"?
We have all done this, I did it routinely until I became aware that I was violateing the UBC and my local fire prevention code. Since then I have noticed it as a violation and have to admit seeing it thousands of times.
Strip malls and commercial lease warehouse spaces are a great example. The individual tenent spaces are almost always seperated by two hour firewalls. How many times have you added cut-ins to those division walls without being aware that you were violating the code and opening yourself to liability?
