burial depth under concrete driveway

[suemarkp]

Another way to think about this would be to look at line 7 where it talks about airport runways. Most runways are thick concrete. But that line is also restricting the (typically grassy) areas adjacent to the runway that are limited access. All methods must be 18" down in row 7. Do you think you could put a rigid conduit 6" below the runway or adjacent area if you covered it in 2 extra inches of concrete (row 2)? I wouldn't think so, but agree this table, like others, can be ambiguous.

 

[kwired]

Another way to think about this would be to look at line 7 where it talks about airport runways. Most runways are thick concrete. But that line is also restricting the (typically grassy) areas adjacent to the runway that are limited access. All methods must be 18" down in row 7. Do you think you could put a rigid conduit 6" below the runway or adjacent area if you covered it in 2 extra inches of concrete (row 2)? I wouldn't think so, but agree this table, like others, can be ambiguous.

some small airports just have grassy area for a runway, but they usually not designed for nor are they long enough to land a 747 either.