Pg 44 of the nov NECA guide's 314.22 states the 'significance' of the 02' change as...

Installing surface-mounted boxes over existing flush boxes, to make aditions to electrical systems is no longer permitted.
This revision permits surface extensions to be made only from flush-mounted boxes with extension rings.

HUH? What?!


314.22 Exposed Surface Extensions.
Surface extensions from a flush-mounted box shall be made by mounting and mechanically securing an extension ring over the flush box. Equipment grounding and bonding shall be in accordance with Article 250.
Exception: A surface extension shall be permitted to be made from the cover of a flush-mounted box where the cover is designed so it is unlikely to fall off or be removed if its securing means becomes loose. The wiring method shall be flexible for a length sufficient to permit removal of the cover and provide access to the box interior, and arranged so that any bonding or grounding continuity is independent of the connection between the box and cover.

Wow... So what do we do with all those shallow boxes (with the 45º corners) that are imbedded in jenny lynn or brick/block walls?

Regular WireMold Extensions not allowed?

Somebody spell this out for me (darn legalese)...

My supplier still sells lots of those boxes (the 45º cornered kind) regardless of my prompting that they are only legal for phone wire!

This was 370-22 in the '99.

It is confusing, I question the mag article, which is (pix) basicaly outlawing 4 sq extension rings

Are we to read this into it??

guys,
This rule is to prohibit the mounting of boxes over existing flush boxes. When you need to add something on over a flush box, this change is only requiring that you use an extension designed for the purpose. The prohibits the installation of boxes (boxes have backs, extensions have openings it the back that match the size of the opening in the flush box) over flush boxes. This is intended to allow access to the wiring in the flush box without having to remove a box installed on top of the flush box.
Don(resqcapt19)

Oh... Thanks, Don...

I was freakin' there for a minute!