Dear Friends, Sincere best wishes to all of you! I am presently working as a journeyman electrician on the remodeling of an exhibit/shop/promotion for Coca-Cola at Walt Disney World ("CLUB COOL"). On Thursday the job foreman displayed concern that some pendant light fixtures had been installed and the 1" X 8-32 machine screws provided by the manufacturer had not been used to attach the fixture plate to the 4" to round plaster ring mounted on the outlet box. Instead (in most instances) , we had used 1/2" X 8-32 machine screws (industry standard, and produced by a major manufacturer) to secure the fixture plate to the plaster ring. In every instance there was direct metal to metal contact between the fixture plate and plaster ring, and at least 1/4" of the machine screw was visible inside of the box. However, the foreman claimed that since the 1" X 8-32 machine screws provided by the fixture manufacturer was not used, this was a potential violation of the UL listing of the light fixture and potentially exposes the electrical contractor (and individual electrician) to increased liability. Now, of course, there was no question that unauthorized "field alterations" to fixtures, devices or other equipment will, in fact, violate the provisions of that items UL listing. For instance, failing to use the provided light fixture installation plates will render the UL listing invalid because such plates are necessary for heat dissipation, grounding and/or other purposes. But, the specific issue here was whether or not the act of not using the factory provided screws was a violation. Have you any specific knowledge or comments concerning this issue. If possible, a speedy answer would be very much appreciated. Thank you very much and take care!
(personal contact info removed - replies can be made here or through the email link ( ) provided)
[This message has been edited by Webmaster (edited 10-22-2005).]
You want an official answer, you'll have to go to UL.
As I understand the UL standards, the manufacturer is required to supply hardware...things like wire nuts and screws. You are NOT required to use those specific parts- they just have to be there, in the box.
Unless the screw were something special.... Like stainless, or some other type of alloy, for the specific purpose of bearing shock, vibration, of additional weight, then I could see an issue. But if that were the case, you you would be using a larger screw anyway. Like a #10 or 1/4/20, and lock-tight.
And yes, I often don't bother with them, (the ones that come with fixtures.) they are usually of inferior quality.
[This message has been edited by e57 (edited 10-23-2005).]
Mark Heller "Well - I oughta....." -Jackie Gleason
Since you can sue anybody for anything, anything that you do exposes you to potential liability. *grin*
The only part of the screw that is 'doing any work' is the part that extends from the head to the part that is engaged in the thread, and perhaps a tinsy bit past to support the last bit of engaged thread. The rest of the screw is just 'extra'.
One could argue that using a longer screw than necessary is 'bad workmanship' because the extra length of screw could puncture conductor insulation. If you go and change all of these screws to the supplied length, and damage a wire, then you would be exposed to potential liability for following poor installation practise.....
I end up going the other way a lot, using shorter screws. If you have an EMT connector in a handy box the device screws are going to be too long. (I still like sleeving NM on a block wall vs the standoffs) I know you can cut them but it is just as easy to simply use the right screw in the first place. I agree with E57, the screws included with equipment is more likely to be chosen based on price than quality. Some are very crude and not even a good fit in the threads.
It's been my experience that the fixture screws seem to be metric because they don't grip the box threads properly. I think you could (and should) argue that using alternate screws is better than the original.
I really don't think the UL listing was affected by alternate screws. What would you do if the box had 10/24 screw holes? Use the 8/32's just because they came with the fixture...I don't think so.