National Electrical Installation Standards

Standards as High as Your Own

Tuesday, February 27, 2018


Is it required to seal the ends of spare conduits that leave a panelboard? When a panel is recessed in a wall the installer often stubs up a few ¾” EMT conduits that just come up above the lay in tile ceiling with a stub 90.

Best Regards, Jim Dorsey



Hey Jim thanks for your question. Raceways must generally be installed complete between enclosures as stated in 300.18(A) and be mechanically continuous as stated in 300.12 - before installing conductors. Openings in enclosures must be closed as stated 110.12(A) and some could argue that the interior of the raceway is a hole in the panelboard. Capping or sealing the end of the raceway is easy to do and will help keep out debris and unintended inhabitants but there is not a specific rule to point to.

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