brother
Senior Member
I remember there was a time when we didn't need to support emt with short runs of 24 inches. Then the code changed and took that away, What was the reason behind that? nec 358.30 (A) and (B)
EMT Support 358.30 why was it changed
- Thread starter brother
- Start date
- Location
- New Jersey
- Occupation
- Journeyman Electrician
The reason is stupidity on the part of the CMP. There was one code cycle the 2008 {250.30(C)} where short, unbroken sections of EMT (18" or less) did not require support. The next code cycle that was removed. If that isn't stupid I don't know what it.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
In many cases, the conduit ends up supporting the support.
Jaybone812
Senior Member
- Location
- South shore. Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
I would argue a piece of emt less than 36” between two boxes is securely fastened in place. The boxes are required to be rigidly secured to the surface , the emt fitting/connectors on both ends secure the conduit to both boxes,
I consider that securely fastened in place within 3’ . It’s def not going anywhere and adding a one hole does nothing , that’s my opinion
brother
Senior Member
Wowl. lol I guess we will have to try to correct the stupidity. As far as Im concerned if they can allow a conduit to be supported at 3ft, (5ft in some instances) then why can we not have an unbroken ( no coupling) emt between to boxes with the same rule?
Reason this came up I had a situation where we had a 'technical' debate at work about a short run of emt between 2 boxes and its a warehouse type no finished wall just studs. So the vertical run is just under 24 inches, box to box. open stud, I was of the interpretation that a support was not needed because of the exception NEC 2023 358.30 No.1 .......When structural members do not readily permit fasting within 3ft.
Heavy emphasis on the 'readily permit'. LOL. He says readily permit is not defined, but readily accessible is. he claims the studs can permit install a support.
I view 'readily' is being almost existing and not needing cross bars or wood or other installs to put a support. lo.
Jaybone812
Senior Member
- Location
- South shore. Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
Well in terms of exception 1 I think he was right and it was not applicable, you were running parallel with the framing members so you have every opportunity to use the stud to secure the emt , 358.30 (a)exception 1 is intended to apply to conduit ran perpendicular to ceiling framing members , if the roof supports spanned 5’ and yiu put a box on one rafters you wouldn’t have to drop a support within 3’ you could secure the conduit at the structural member 5’ from the box as long as it was a unbroken length of conduit
That being said i like I mentioned in my prior comment I feel that 2’ piece of emt you had between two boxes satisfied 358.30(A) and was securely fastened in place
Attachments
- Location
- Illinois
- Occupation
- retired electrician
It was removed because of PI from the IAEI that said the rule in the 2008 code required additional supports and the CMP agreed. The PI for the 2008 rule called for a 36" length and the CMP accepted in part by changing the 36" to 18".
There have been a number of attempts to fix this issue for EMT, IMC, and RMC. They all had the same rule in the 2008 code.
Most inspectors ignore the actual code language and permit a straight, unbroken, 36" length to be supported by the conduit terminations.
There have been a number of attempts to fix this issue for EMT, IMC, and RMC. They all had the same rule in the 2008 code.
Most inspectors ignore the actual code language and permit a straight, unbroken, 36" length to be supported by the conduit terminations.
Jaybone812
Senior Member
- Location
- South shore. Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
I read PI 2359 as well as both yours and Mr Holts Pc’s regarding this and I would’ve thought your pc would be accepted based on committee statement resolving PI 2359 when they said up to 3’ is already allowed , but the pc proposed the language to clear up any confusion
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brother
Senior Member
Who is P ??
Jaybone812
Senior Member
- Location
- South shore. Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
PI- public input
IAEI submitted a Public input stating the rule in 2008 required additional supports, and it passed , the cmp accepted what they proposed
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brother
Senior Member
They may have or have not intended it that way, but that is not what it says. ;-) One can say the same as about the ceiling, they could have ran it parallel instead of perpendicular, it would look weird but it can be done. lol ;-) So there goes my interpretation.
I agree with you, the 3ft, or my honest opinion the 5ft should be OK with 2 terminations of boxes.
Jaybone812
Senior Member
- Location
- South shore. Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
While I will say the language used in the exception may not be completely clear as to intent, but the explanatory material from the nfpa link enhanced content speaks to intent , and I’ve always read it the same way
If you’re running parallel with framing like you were, how does the framing prevent you from securing the conduit where required?? You are running along the framing even if you’re in the middle of the bay you have access to framing members to use a TSGB-16 or offset over to the actual stud and strap the conduit to the stud
Exception 1 may not specifically say when running perpendicular to structural framing members , but what it does say is you can increase the distance to 5’ when structural members don’t readily permit fastening within 3’ .
you have a short raceway between 2 boxes that runs parallel to the studs in the bay and both boxes are secured to the framing parallel to the raceway . How can you say the framing doesn’t readily permit fastening within 3’ when you’re running with the framing , and the boxes where you terminate the conduit are both secured to that parallel framing ? The framing definitely allows you to securely fasten the conduit anywhere between the boxes
So exception 1 is not applicable, but that doesn’t mean you were required to add a means of securement , I feel it’s securely fastened in place with fittings on each end that secure the conduit to each box that is rigidly secured to the surface , the rule doesn’t say it must be a strap , just says securely fastened within 3’ of box/enclosure/conduit body
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pipe_bender
Senior Member
- Location
- Boston
- Occupation
- Electrician
There are tons of products now for supporting EMT, for a run like that I'd use one of these;
hbiss
EC, New York NEC: 2017
- Location
- Little Falls, New York NEC: 2017
- Occupation
- EC
Jaybone812
Senior Member
- Location
- South shore. Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
I honestly don’t know , Don is the one who mentioned the IAEI PI that was proposed and accepted , brother asked Don who P was I was just explaining it was a PI @don_resqcapt19 how did the Cmp justify acceptING the proposal from the IAEI ?
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
- Occupation
- Electrician
I am still not clear on what happened. So the IAEI said the rule that was in the 2008, that exempted support for short sections between enclosures, required MORE supports?
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
Ryan Jackson submitted a proposal from Mike Holt to clarify the support rule. The final rule caused a lot of issues! So it went away.
- Occupation
- Licensed Electrician
The justification was that the change that said you don't need a strap for 18" of pipe meant that you needed to have one and that would make an inspector's job more difficult. I'm going off of memory and using my own words, but it was something as crazy as I am making it sound.
- Location
- Illinois
- Occupation
- retired electrician
But the result is you need a strap for a 2" length now.
jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
"Fastened in place" is defined by the NEC merely as needing tools to remove. "Securely" is not defined, and is up to the AHJ to interpret per dictionary definition or common understanding.
Thus if the length of EMT between boxes is less than 3ft, and the AHJ approves it as 'secure' there is no code requirement for additional straps, since we can assume the EMT is 'fastened in place' by properly installed connectors.
An exception citing 18 inches would imply that sections between 18 and 36 inches require strapping even if they are otherwise securely fastened in place. So I think that was the problem.
So, my position is that the code *allows* EMT between boxes up to 3ft, without a strap, so long as it's 'secure'. In my book that's going to require the boxes to be secure, and for it to be straight without a coupling, as most agree in practice.
Thus if the length of EMT between boxes is less than 3ft, and the AHJ approves it as 'secure' there is no code requirement for additional straps, since we can assume the EMT is 'fastened in place' by properly installed connectors.
An exception citing 18 inches would imply that sections between 18 and 36 inches require strapping even if they are otherwise securely fastened in place. So I think that was the problem.
So, my position is that the code *allows* EMT between boxes up to 3ft, without a strap, so long as it's 'secure'. In my book that's going to require the boxes to be secure, and for it to be straight without a coupling, as most agree in practice.