USE/USE-2 Restrictions

[sffrog]

I understand the requirement that single- and multiconductor Types USE and USE-2 are not suitable for use in premises or aboveground except to terminate at the service equipment or metering equipment. What I am curious about is why this restriction exists. I'm sure there was a good reason, but what was the reasoning? BG

 

[Dennis Alwon]

Firstly, there are some USE cables that are suitable for indoor and outdoor use. I thought that was called USE-2 but I may be wrong.

The reason is that USE simply has not been tested for a vertical flame rating. Being it is used mostly for distribution I believe the manufacturers don't feel the necessity to have it tested for the VFR. My opinion, of course

 

[jumper]

Here is a link to add to what Dennis said.
http://www.southwire.com/commercial/CURhhRhwUse.htm
Also look up USE in T310.13. It shows the lack of flame retardant rating needed for interior use.

 

[cpal]

Here is a link to add to what Dennis said.
http://www.southwire.com/commercial/CURhhRhwUse.htm
Also look up USE in T310.13. It shows the lack of flame retardant rating needed for interior use.

Probably should add if the cable DOES NOT have other additional insulation designators such as (but limited to) RHH RHW THWN XHHW and it ONLY has USE stamped on it it is NOT suitable(allowed) for interior use. The Proposal to the 96 and 99 NEC mentioned as Dennis stated the porduct has not been submitted for a verticle flame test. As I understand without such a test the cables flame spread and smoke producing effects(to name a few) have not been investigated.

 

[LarryFine]

I thought that was called USE-2 but I may be wrong.

I believe the -2 suffix indicates that the wet temperateure rating is the same as the dry rating.