The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Featured:

2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
Members: Non-Members: Did you know?
by Admin
Today at 02:34 PM
Safety at heights?
by HotLine1
Yesterday at 08:51 PM
International Wire Colour Codes
by Texas_Ranger
Yesterday at 03:29 PM
Looking for older post
by Texas_Ranger
Yesterday at 03:22 PM
Last time to chat here
by Trumpy
01/20/17 11:41 PM
New in the Gallery:
Desk-mounted "power-board"
Shout Box

Top Posters (30 Days)
Admin 36
HotLine1 20
Ruben Rocha 17
gfretwell 16
Trumpy 15
Who's Online
1 registered (Admin), 83 Guests and 10 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#98902 - 06/22/06 04:06 PM Burial Depth
George Little Offline
Member
Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
What is the burial depth for EMT? Assume it has the proper corrision protection.
_________________________
George Little
Top
2017 / 2014 NEC & Related Books and Study Guides
#98903 - 06/22/06 04:10 PM Re: Burial Depth
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Darn it all George, can't you ask a simple question at least once in a while?


Bob
_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts
Top
#98904 - 06/22/06 04:13 PM Re: Burial Depth
George Little Offline
Member
Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
That wouldn't be any fun Bob. Got these contractors asking me these wierd questions and I like to share
_________________________
George Little
Top
#98905 - 06/22/06 04:21 PM Re: Burial Depth
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
George you know I am kidding, I like the questions you bring us.

I am going to take door number...er column number 3 of Table 300.5 "or Other Approved Raceways"

Don't know if I am right but it appears the only option.

Bob
_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts
Top
#98906 - 06/22/06 05:46 PM Re: Burial Depth
renosteinke Offline
Cat Servant
Member
Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
EMT...under what?

Corrosion protection is a BIG "if." That said.... and bear with me, I am going by practical experience and NOT code here...these would be my "EMT rules:"

1) First foot into ground gets pipe wrap;
2) Passing under sidewalk or slab, at least 4" below either (so the concrete saw misses it);
3) Area totally unsuitable for walking over, due to landscaping, etc,... at least below the irrigation pipes; and
4) Under anything even vaguely resembling a road or parking lot, 2 ft!; and, finally-
5) Always totally inadequate for supporting any box, anywhere. Better make a frame from strut.
Top
#98907 - 06/22/06 06:41 PM Re: Burial Depth
ShockMe77 Offline
Member
Registered: 06/11/05
Posts: 823
Loc: Rahway, New Jersey
George, you have licensed elecricians ask you how deep EMT has to buried?
Top
#98908 - 06/22/06 10:53 PM Re: Burial Depth
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9066
Loc: Estero,Fl,usa
I have never seen EMT corrosion protection I "judged suitable for the condition." of being buried in Florida. I have dug up EMT that was in the ground less than 5 years and it was a rusty trail of sand with THWN in it.
The only reason you would know it was EMT was the zinc connectors. We do have pretty salty ground water tho, typically 5 PPT or so, west of 41.
_________________________
Greg Fretwell
Top
#98909 - 06/23/06 08:24 AM Re: Burial Depth
dlhoule Offline
Member
Registered: 04/28/05
Posts: 71
Loc: Saline, MI 48197
358.10 Uses Permitted.

(A) Exposed and Concealed. The use of EMT shall be permitted for both exposed and concealed work.

(B) Corrosion Protection. Ferrous or nonferrous EMT, elbows, couplings, and fittings shall be permitted to be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences where protected by corrosion protection and judged suitable for the condition.

(C) Wet Locations. All supports, bolts, straps, screws, and so forth shall be of corrosion-resistant materials or protected against corrosion by corrosion-resistant materials.

Where does it say anything about having to be buried? I can be run along the top of the ground if it is suitable for the condition. Like where outside wall or foundation meets the finished grade. Maybe 1/2" lower if you don't want it visible.

Now if you'll tell us what this is being used for maybe we can provide a good answer.

You'll notice I said we, Not I.
Top
#98910 - 06/24/06 01:29 PM Re: Burial Depth
jes Offline
Member
Registered: 07/12/02
Posts: 103
Loc: CT
George, I would say Table 300.5 column 3 or 4 depending on the location, and that all other 300.5 requirements are met. This link also provides some info re the subject of corrosion protection for EMT:
http://www.steelconduit.org/pdf/ConGuide.pdf
Top
#98911 - 06/26/06 07:00 PM Re: Burial Depth
Steve T Offline
Member
Registered: 02/14/01
Posts: 312
Loc: Oak Park, IL, USA
dlhoule--You make a very good point, but you cannot bury anything a half inch below the ground. Once something is 'direct-buried' (as opposed to indirect-buried) 300.5(A) kicks in and the appropriate depth for the situation kicks in. Unless under a building, the minimum depth would be 4".

What makes me wonder is that service conductors that are buried less than 18" below grade do not need a warning ribbon, but 18" or more does. What sense does that make? 300.5(D)--Protect the person digging a large hole, but the poor gardener can get fried?
Top
Page 1 of 2 1 2 >


ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals