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Tom Horne, Electrician

Doug Miller wrote:
In article , wrote:
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite certain
this does not meet code.

Yep, you're right, doesn't meet the National Electrical Code (NEC).

Understand, however, that your local jurisdiction may have requirements that
differ from the NEC, so for the definitive answer regarding what's legal where
you live, call your local electrical inspector. The local requirements can be
either more stringent than the NEC (Chicago, for example) or less so (certain
areas of rural Indiana, for example -- I used to live in a place where there
was _no_code_at_all_. Scary.)

I always did my wiring to Code even though there was no legal requirement to
do so, and if I had an electrician working for me, I'd insist he do the same.

Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Having said all that, though, here's what the NEC says about minimum
cover for buried electrical installations (assuming that we're talking about
burying it in your yard, not under a driveway, sidewalk, basketball court,
etc):
- direct burial: two feet
- in rigid nonmetallic conduit (PVC): eighteen inches
- in EMT (aka thinwall) -- don't know -- can't find that listed
- in Rigid Metal Conduit (aka thickwall) or Intermediate Metal Conduit: six
inches

Note also that if the circuit is 120V, *and* not more than 20A, *and*
protected by a GFCI, it may be as shallow as twelve inches (six if in RMC or
IMC).

But under *no* circumstances does it meet Code to direct-bury a UF cable as
shallow as only four inches.

Not quite true. When UF is used to run low voltage wiring supplied
through a laboratory listed power limited supply it can be run at quite
a shallow depth of bury. That's the problem with these types of
questions. We have to assume so much to answer them.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison