Is a panel door the same as a dead front?

No. The dead front is the interior barrier with breaker handle openings that guards live parts. The door is the outer finish piece over the handles.

Do I have to fill empty breaker slots?

Yes. NEC 408.7 requires unused breaker openings to be closed with identified closures providing protection substantially equivalent to the enclosure wall.

What is the difference between a dead front and a panel cover?

Q: What NEC section requires panelboards to be dead front?

NEC 408.38 requires panelboards to be mounted in cabinets, cutout boxes, or enclosures designed for the purpose and to be dead front.

A dead front is the barrier that keeps you from touching energized parts while the panel is in service. Article 100 defines dead front as without live parts exposed to a person on the operating side of the equipment. In a loadcenter, the dead front is the removable metal plate with the breaker handle openings, sometimes called the interior cover or the trim. The panel cover in common usage is the hinged door, or the door and frame assembly, that finishes the enclosure and hides the breaker handles.

Why the distinction matters on an inspection

Removing the door leaves the equipment dead front. Removing the barrier with the breaker handle openings exposes the bus, the lugs, and the terminations, and the equipment is no longer dead front. That is the difference between opening a panel to read the directory and opening a panel for energized work.

Section 110.27(A) requires live parts of electrical equipment operating at 50 volts or more to be guarded against accidental contact by approved enclosures, by location in a room or vault accessible only to qualified persons, by elevation, or by permanent partitions or screens. The dead front is the approved enclosure element that satisfies that section on a panelboard.

Panelboard specific language

Section 408.38 requires panelboards to be mounted in cabinets, cutout boxes, or enclosures designed for the purpose and shall be dead front. Section 408.36 requires each panelboard to be protected on the supply side by an overcurrent protective device having a rating not greater than that of the panelboard, with the listed exceptions for individual protection and for existing installations.

Section 408.7 requires unused openings for circuit breakers and switches to be closed using identified closures, or other approved means that provide protection substantially equivalent to the wall of the enclosure. A missing breaker with an open slot in the dead front is a violation of 408.7 and of 110.12(A), which requires unused openings other than those intended for the operation of equipment or for mounting purposes to be effectively closed.

Related terms you will hear

Trim is the manufacturer term for the assembly that includes the dead front and the door on a commercial panelboard. A surface trim covers the enclosure edges, a flush trim overlaps the finished wall. A cover on a junction box or a wireway is a different item entirely and is governed by 314.28(C), which requires all pull boxes, junction boxes, and conduit bodies to be provided with covers compatible with the enclosure and construction.

Section 408.43 requires panelboard enclosures with front covers to be arranged so the front cover cannot be installed if the main circuit breaker or other device is in a position other than the intended one, which is the rule that prevents an upside down main from being hidden behind a trim.

Field takeaway

Dead front is the safety barrier over live parts. Cover or door is the finish piece over the handles. Both belong on the panel, unused breaker openings must be filled with identified closures, and pulling the dead front puts you into energized work territory under NFPA 70E.