Directional Boring Warning Ribbon

[Shockhoss]

We are pricing to move an overhead service to underground, I inform AHJ, local inspector for the area that we are considering directional boring due to the circumstances. He asks how we plan on putting the metallic direct burial tape or some type of warning tape 12" above the bore for future indication. I see NEC 2017, 300.5(D)(3) about direct burial cables requiring "Warning Ribbon" but nothing in 300.5(K) in directional boring that is requiring it... we fully intend on installing PVC sch. 40 minimum for the bore sleeve.

Looking for some advice or ammunition to allow us to consider this for the customer and future projects, we've never been questioned on this before, has anyone else?

 

[kwired]

"shall have their location identified by a warning ribbon that is placed in the trench at least 300mm (12 in.) above the underground installation"

What trench?

Also ask him if you did bore in a warning ribbon, how is he going to confirm it is in the right place?

But also back up a little and read (D) - this only applies to direct buried cables and conductors anyway. You were going to install a raceway.

 

[Shockhoss]

That's my interpretation as well, I've gone ahead and asked the inspector what code reference he's looking at that's requiring the warning ribbon so that I can learn from this.. we'll see what he comes back with...

have you ever been questioned on the warning ribbon and directional boring?

 

[ptonsparky]

Not required by any knowledgeable inspector. HUA strikes again.

 

[kwired]

Again 300.5 (D) states direct-buried conductors and cables. So unless there is mention of the ribbon warning elsewhere it is not required by this section if conductors are in raceway.

 

[ptonsparky]

That's my interpretation as well, I've gone ahead and asked the inspector what code reference he's looking at that's requiring the warning ribbon so that I can learn from this.. we'll see what he comes back with...

have you ever been questioned on the warning ribbon and directional boring?

Way better than accusing him of outright ignorance.

And No, our code meetings all brought up that exact scenario. No tape.

 

[kwired]

Way better than accusing him of outright ignorance.

And No, our code meetings all brought up that exact scenario. No tape.

that might depend on how often he is wrong

And if he actually cites codes or mostly says things like "I/we like to see ....this way"

 

[don_resqcapt19]

CMP 3 says the ribbon is not required for directional bored service conductor installations. The following two proposals to require ribbons for that application were rejected in the 2008 code cycle. this color indicates text that the proposal would delete

3-38 Log #678 NEC-P03 Final Action: Reject
(300.5)
____________________________________________________________
Submitter: Jamie McNamara, Hastings, MN
Recommendation: Revise as follows:
300.5 Underground Installations. ……..
(D) Protection from Damage. Direct-buried conductors and cables shall be
protected from damage in accordance with 300.5 (D)(1) through(D) (3) (4) .
(1)…..
(3) Service Conductors. Underground service conductors that are not encased
in concrete and that are buried 450 mm (18 in.) or more below grade shall have
their location identified by a warning ribbon that is placed in the trench at least
300 mm (12 in.) above the underground installation.
(3) (4) Enclosure or Raceway Damage. …….. (E) …….
(G) Service Conductors. Underground service conductors that are not encased in concrete or in metal conduit and that are buried 450 mm (18 in.) or more below grade shall have their location identified by a warning ribbon that is placed in the trench at least 300 mm (12 in.) above the underground installation.

Substantiation: To require direct-buried conductors and nonmetallic conduits (PVC) containing service conductors to have identification ribbon. When excavating around nonmetallic conduits buried 450 mm or deeper, the conduits and the conductors inside are often damaged and striped, exposing the excavator to hazards, before being recognized as conduit and conductors.

Panel Meeting Action: Reject
Panel Statement: Direct buried service conductors are much more easily damaged, even when the operator is scratching the surface of the trench to locate the conductors, than when the conductors are installed in a raceway. A backhoe operator can damage any raceway system if the operator is not paying attention and has no idea that anything is buried below.
All utility companies have a service that will mark the ground directly above the service conductors, whether the conductors are directly buried or not, so anyone digging in that area will be less likely to damage their conductors. Cable locators should be used before any trenching or backhoe work is started in an area where service conductors may be buried. The primary concern for service conductors is providing an indicator, such as a warning ribbon, for direct burial cables, especially where those cables have no other form of protection.
Schedule 80 PVC could certainly be used as a protection method for underground service conductors or cables. Restricting the protection to metal conduit would not recognize this alternative protection method. A backhoe operator could damage cables or conductors in any wiring method installed but a raceway will provide some level of protection for these service conductors. Direct burial cables are not protected, so a warning ribbon is a method to help identify the location for these conductors and provide some warning that service cables are located below.
In addition, the result of this proposal would be to delete the present 300.5(D)(2) because it has not been shown as retained, and the reason for doing so has not been provided.
Number Eligible to Vote: 13
Ballot Results: Affirmative: 12 Negative: 1
Explanation of Negative:
CASPARRO, P.: As the panel statement indicated, a backhoe operator can damage any raceway system if the operator is not paying attention and has no idea that anything is buried below, therefore, a warning ribbon placed 12 in. above the underground installation would alleviate this problem, thus saving unnecessary damage and possible bodily harm.

3-49 Log #2232 NEC-P03 Final Action: Reject
(300.5(D)(3))
____________________________________________________________
Submitter: Donald A. Ganiere, Ottawa, IL
Recommendation: Revise as follows:
(3) Service Conductors. Underground service conductors that are not encased in concrete and that are buried 450 mm (18 in.) or more below grade shall have their location identified by a warning ribbon that is placed in the trench at least
300 mm (12 in.) above the underground installation.

Substantiation: The potential hazard from a “dig-in” accident is not changed by the method used to install the conductors. If service conductors installed in a trench present a hazard, then so do service conductors installed by directional
boring or other “trenchless” methods. The warning ribbon requirement should apply to all underground service conductors or to none of the underground service conductors. The panel should not consider the additional costs required to install the warning ribbon when “trenchless” installation methods are used. The only consideration should be the safety of the system, and if trenched in service conductors require a warning ribbon for safety reasons, then so do service conductors installed using other methods of installation.

Panel Meeting Action: Reject
Panel Statement: The only way to install a warning ribbon 12-inches above a bored hole containing service conductors would be to drill an additional hole with the ribbon inserted in the hole and pulled through from one location to
another or to dig a trench to a depth 12-inches above the cable. In addition, since the ribbon would be installed in a drilled hole, the inspector would not be able to verify the depth of the ribbon as being 12-inches above the service conductors.
Number Eligible to Vote: 13
Ballot Results: Affirmative: 12 Negative: 1
Explanation of Negative:
CASPARRO, P.: See my explanation of negative vote on Proposal 3-38.

 

[GoldDigger]

The OP said that there would be a sleeve, not a raceway. How does that affect the argument that it is not direct burial?

 

[don_resqcapt19]

The OP said that there would be a sleeve, not a raceway. How does that affect the argument that it is not direct burial?

The requirement in 300.5(D)(3) says the ribbon is only needed where the directly buried cables are installed in a trench. There is no trench with directional boring.

It is my opinion, any time the outer jacked of a cable or the conductor insulation is not in physical contact with the earth, the cable or conductor is not directly buried.

 

[hillbilly1]

Wait till you have an inspector ask how deep is it? We had the locator come back out and give an approximate depth to satisfy the inspector.

 

[kwired]

The OP said that there would be a sleeve, not a raceway. How does that affect the argument that it is not direct burial?

He said PVC Sch 40 bore sleeve - possibly could be electrical PVC is being pulled in by the boring company, EC pulling conductor through that sometime afterward. Most boring guys like to pull in HDPE but can pull about anything you want when retracting the boring rods.

 

[kwired]

Wait till you have an inspector ask how deep is it? We had the locator come back out and give an approximate depth to satisfy the inspector.

Unless he has legitimate reason think I am trying to pull one over on him, he better accept some simple observations and trust that a contractor generally tries to do things right and give him the benefit of doubt until contractor proves he isn't trustworthy. Then it is fair to question anything and everything. No way he is going to know how deep it is for certain if he watched them bore it, other than to trust what the instruments say, and they are generally very accurate with that kind of equipment. Can usually trust them to install at a certain depth more than you can trust a trencher operator to maintain requested depth. Often if there is any doubts they go deeper before they go shallower with boring equipment, unless they know there is something deeper to potentially hit.

 

[Shockhoss]

The following is a snapshot of the email response that I received from the inspector this morning.... is this where AHJ pulls rank?

Mr. Temple
300.5 Underground Installations

D ) Protection from Damage - is referring to all types of underground installations.

Trenching is the most common method used for installing electrical wiring so
“trench” is instructing the installer to include the warning ribbon.

D) 3) “Service” Conductors. The intent of this extends further than other types of underground installations because;

“warning ribbon reduces the risk of an accident, such as electrocution or an arc-flash incident, during excavation near underground service conductors that are not encased in concrete, because these circuits are not protected from short circuit or overload.”**

If directional boring can be done for the conductors then warning ribbon can be bored just above the Service Conductors.

The ultimate goal is to ensure the safety of the general public.

I’m still insisting on a warning ribbon if this Service is indeed moved underground.
Sincerely,
-------

 

[RichB]

The following is a snapshot of the email response that I received from the inspector this morning.... is this where AHJ pulls rank?

Mr. Temple
300.5 Underground Installations

D ) Protection from Damage - is referring to all types of underground installations.

Trenching is the most common method used for installing electrical wiring so
“trench” is instructing the installer to include the warning ribbon.

D) 3) “Service” Conductors. The intent of this extends further than other types of underground installations because;

“warning ribbon reduces the risk of an accident, such as electrocution or an arc-flash incident, during excavation near underground service conductors that are not encased in concrete, because these circuits are not protected from short circuit or overload.”**

If directional boring can be done for the conductors then warning ribbon can be bored just above the Service Conductors.

The ultimate goal is to ensure the safety of the general public.

I’m still insisting on a warning ribbon if this Service is indeed moved underground.
Sincerely,
-------

Time to escalate to his boss

 

[Shockhoss]

Initially his boss is on his side, I asked right after I was informed about it. I haven't followed up with him again since the initial shock of the request. It gets to be tricky that we try to create a good working relationship with inspectors, built on trust. Such a fine line, do inspectors hold grudges, or if a discussion happens and he sees it like everyone on this forum sees it, we could perhaps create a better working relationship??? hard to tell, walking fine lines

 

[K8MHZ]

" If directional boring can be done for the conductors then warning ribbon can be bored just above the Service Conductors. "

Is this even possible?

 

[Shockhoss]

I'm guessing we need to include (2) bores for future instances like this. While discussing this with a co-worker, an option we had was...direct bore the service at 36", then direct bore a conduit for the data conduit at 24" and pull a metallic tape in with it in same hole, as long as they follow the path???

Who knows???

 

[hillbilly1]

Is this in North Carolina? They seem to do some weird things there! LOL!

 

[Shockhoss]

That's funny..but no, Louisville KY