Conduit run below Class 1 Div 2

[travski06]

I have been wiring convenience store/ fuel stations for the last 10 years, and have always put a sealoff on each end when running below the fuel dispensers.
ex. from the building to a light pole through the fuel island. Is a seal needed if I have at least 2 feet of cover (514.8 ex. 2) and is just passing below the class 1 Div 2 and not penetrating vertically through it? Just wondering because you can run pvc if it has at least 2 feet of cover and I do not believe that below 2 feet is a classified location if so I cannot locate it in the great book. Thanks for your input!

 

[rbalex]

You are displaying a good understanding of both the rules and the reality of the situation as it applies to Article 514. The rules still require a seal; the reality is the underground is not classified as recognized by the major revision of Figure 514.3 between the 2002 and 2005 NECs. The reason is a bit tougher to explain.

Section 514.8 Exception 2 applies strictly to permitting PVC underground rather than requiring threaded RMC or IMC below locations classified under Article 514. The sealing requirements remain unchanged.

The rules of Article 514 contain a great deal of material extracted from NFPA 30A. The Technical Committees for Article 514 (Code Making Panel 14) and NFPA 30A have not reached complete agreement on a few things and the current condition of Article 514 is more or less the consensus at the moment; i.e., both TCs have agreed they can live with it.