Adding a 20 amp subcircuit (120V) to furnace room to turn it into a workshop. Initially it will have one duplex and 2 fourplex receptacles, the fourplex receptacles will be on cement walls, the duplex will be on a stud.
I know that for the duplex I just need to staple the cable back far enough so that if someone ever puts drywall up there will be no danger of hitting the wire with a drywall screw.
Section 334.15.c of the NEC 2011(which the state of MI uses) says
…Nonmetallic-sheathed cable installed on the
wall of an unfinished basement shall be permitted to be
installed in a listed conduit or tubing or shall be protected
in accordance with 300.4.
I'm assuming they mean UL Listed conduit or tubing, which the smurf tube I'm looking at is. Am I correct in this assumption? Also, is this common practice, using ENT on exposed walls to a metal box? I know that the metal box (and metal tubing if I used it) has to be grounded, just making sure I'm not being too unorthodox with solution, or going against code.
Best Answer
You'll have to check with the Authority Having Jurisdiction, but I'd say "smurf tube" on a wall in a shop is a no no.
National Electrical code allows ENT for exposed work, but not where subject to physical damage. Which means if you're trying to protect your cable from physical damage, you can't use ENT (unless you protect the ENT from physical damage as well).
If you don't want to use metal conduit, schedule 80 PVC conduit is identified for areas of physical damage.