Electrical Metallic Tubing (EMT)

EMT bends easily and goes up fast, which is why you see it running the ceilings of every strip mall and warehouse. The fittings, not threads, hold it together and complete the ground path.

The catch is the fittings: they have to be the right type and tight. In damp spots you need raintight compression fittings, and every connector has to actually clamp for the ground to hold.

When it applies

EMT is the workhorse raceway for dry, protected commercial and industrial interiors — exposed on walls, above accessible ceilings, in mechanical rooms. It installs fast, gives good physical protection, and with the right fittings can serve as an equipment grounding path.

Common mistakes

• Using standard compression fittings in a wet or corrosive area where raintight or PVC-coated components are required.
• Over-bending a run past the equivalent of four quarter bends between pull points and then fighting the wire on the pull.
• Cutting tubing and leaving a burred edge that shreds insulation as conductors go in.

In the field

I ream every cut end without exception. A thirty-second pass with the reamer keeps a sharp lip from nicking a conductor, and a nicked conductor in a metal raceway is a fault waiting for the worst possible moment.