LMFC type EF use in Class 1 Div 2 hazardous location (brand anaconda)

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DA72

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Gibbstown NJ
A large construction project has recently completed at my work. Due to the volume of flammable solvents able to be contained in the area the room is classified as Class 1 Div 2 location. Where as some areas around man-ways and ports are class 1 div 1. Now in the commissioning phase, the safety dept. in conjunction with safety consultants are going through Process Safety Management startup required by NJ for the amount of flammable solvents that can be contained in that room at any one time. Recently I discovered during inspections of grounding and bonding what I saw as an issue.

The installing contractor installed LFMC Type EF in all of the room where flexible connections were needed, estimated some 200 locations. The brand Anaconda Type EF is not listed see reference to website and related PDF datasheet for type EF:
http://flexiblewiringconduits.anaco...rade-liquid-tight-flexible-metal-conduit-lfmc

My argument is that in the NEC both 2011 and 2014 Chapter 3 Wiring Methods and Material, Article 350.6 that LFMC and associated fittings shall be listed. Anaconda Type EF unlisted where as type UA is listed.
350.10 points out areas where LFMC can be used IE: (2) 501.10(b) Class 1 Div 2 (2) Flexible connections (3) LFMC with listed fittings.

The Contractor who installed is arguing that it is correct "feels it was installed according to code because of the existence of the double seal offs at each end of LFMC runs. Also they list pictures of NEC articles 501, 501.35(b), and 501.17.

EF issue.jpg

I am not arguing that the installation method was incorrect, just the material they used is not listed to be used in this environment. It does say as in Article 501 (B) (2) Flexible connections (3) liquidtight flexible metal conduit with listed fittings. *Where the code book does not reference listed for the LFMC, just listed for fittings.

Still unsure the design company came in Friday also taking pictures saying he will review over the weekend in the codes, but feels fairly confident it is correct.

I am confused how even with proper bonding, sealoffs, that unlisted anaconda type EF can be allowed?

Can anyone let point out where I am wrong? Or what I should do next in case this problem is a legitimate concern which they fail to correct.
Thank you!

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rbalex

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It doesn't bother me personally; in fact, I made a proposal (rejected) to specifically make it acceptable; but spiraling the bonding conductor around the flex gives several CMP14 members the shakes. They want that bonding conductor as short as possible consistent with the length of the flex.
 

DA72

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Location
Gibbstown NJ
Quite simply, if it isn't listed, it isn't LFMC. See Section 350.6.

LFMC can be either listed or unlisted type. The type has to do with testing of insulating material in specific situations. The gases solvents produce could damage the insulation of unlisted type EF allowing the bare metal to be exposed and wire.
 

rbalex

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LFMC can be either listed or unlisted type...
Not so - no matter what the manufacturer's literature, sales or engineering staff says. If it isn't listed, it isn't LFMC. It's black and white in Section 350.6.
 

rbalex

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Actually, it doesn't even need to be LFMC in Division 2. Plain FMC is suitable. See Section 501.10(B)(2)(2). The essential feature is the armor's interlocking method.
 

DA72

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Location
Gibbstown NJ
Not so - no matter what the manufacturer's literature, sales or engineering staff says. If it isn't listed, it isn't LFMC. It's black and white in Section 350.6.

I get what you are saying that to be LFMC is needs to be listed and tested by UL. as in Type UA LFMC anaconda which represents the codes and uses allowed. But the installing contractor electrical engineer and design firm electrical engineer are arguing that it is acceptable. Do I let this go or could this lead to a potential serious hazard? If so who can I talk to professionally about this?
 

DA72

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Location
Gibbstown NJ
Actually, it doesn't even need to be LFMC in Division 2. Plain FMC is suitable. See Section 501.10(B)(2)(2). The essential feature is the armor's interlocking method.

I disagree per 348.12 (4) and (5) where exposed to material having deteriorating effect on installed conductors such as oil or gasoline. The material that will be contained in excess of 10000 gallons, would be Ethel alcohol, Acelbutate, and Acetone.
 

petersonra

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Northern illinois
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engineer
I get what you are saying that to be LFMC is needs to be listed and tested by UL. as in Type UA LFMC anaconda which represents the codes and uses allowed. But the installing contractor electrical engineer and design firm electrical engineer are arguing that it is acceptable. Do I let this go or could this lead to a potential serious hazard? If so who can I talk to professionally about this?
My off the cuff guess is that there is no serious added risk.

Having said that, it does not meet code, regardless of the area classification. I don't see how you get past that.

Not to pick on you, but I am not sure if it's a good idea for you to insert yourself into this mess. It is something that will have to be dealt with several paygrades up.
 

rbalex

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I disagree per 348.12 (4) and (5) where exposed to material having deteriorating effect on installed conductors such as oil or gasoline. The material that will be contained in excess of 10000 gallons, would be Ethel alcohol, Acelbutate, and Acetone.
That's a legitimate design consideration; however, if you have enough "Ethel alcohol, Acelbutate, and Acetone" in the atmosphere to actually be a concern you might want to reconsider the Division 2 classification too.

EDIT ADD: Remember NO raceway is vaportight, liquidtight or not.
 
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rbalex

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My off the cuff guess is that there is no serious added risk.

Having said that, it does not meet code, regardless of the area classification. I don't see how you get past that.

Not to pick on you, but I am not sure if it's a good idea for you to insert yourself into this mess. It is something that will have to be dealt with several paygrades up.
Bob, the essential concern is grounding/bonding and the raceway construction is critical as I mentioned above.

Odds are the "several paygrades up" will be pressing the OP for his views.
 

DA72

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Location
Gibbstown NJ
My off the cuff guess is that there is no serious added risk.

Having said that, it does not meet code, regardless of the area classification. I don't see how you get past that.

Not to pick on you, but I am not sure if it's a good idea for you to insert yourself into this mess. It is something that will have to be dealt with several paygrades up.

The company I work for is a smaller company growing and doesn't have all the ranks a larger company does. Which is why they hired out a design firm and contractors to install. If the contractors didn't install correctly and the is a hazard. I as lead electrician for the facility am worried for the safety aspect of the building and fellow co-workers. The code specifies hazardous locations and appropriate materials for a reason to protect persons and property. Am I not obligated to use code book and resources for such. If I don't and the designers are wrong or installers, who will point out fault? So far no reason has been given that this is correct installation or safe.
 

DA72

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Location
Gibbstown NJ
That's a legitimate design consideration; however, if you have enough "Ethel alcohol, Acelbutate, and Acetone" in the atmosphere to actually be a concern you might want to reconsider the Division 2 classification too.

EDIT ADD: Remember NO raceway is vaportight, liquidtight or not.

Areas around man-ways, ports, or readily accessible areas are classified class 1 div 1 where wiring in these areas is done the same way. Careful consideration was also put into LEL sensors for explosive limits, ventilation system for evacuation of fumes where spot ventilation is required to remove x amount of cfm's and VFD to maintain a specified static pressure in ducts. There is also a purge system for fast evacuation of fumes for large spills. But all this is only as good as the weakest link. An arc because a breakdown of improper insulation of raceway is my concern.
 

rbalex

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Areas around man-ways, ports, or readily accessible areas are classified class 1 div 1 where wiring in these areas is done the same way. Careful consideration was also put into LEL sensors for explosive limits, ventilation system for evacuation of fumes where spot ventilation is required to remove x amount of cfm's and VFD to maintain a specified static pressure in ducts. There is also a purge system for fast evacuation of fumes for large spills. But all this is only as good as the weakest link. An arc because a breakdown of improper insulation of raceway is my concern.
That's interesting. I'd like to know the engineering standards that were applied. To me, it appears it's a "seat of the pants" WAG.
 

GoldDigger

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...
... An arc because a breakdown of improper insulation of raceway is my concern.
And I think rbalex is stating that failure of an OCPD to open under a ground fault because of an inadequate raceway EGC is something that the CODE requires you to consider too.
 

DA72

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Gibbstown NJ
And I think rbalex is stating that failure of an OCPD to open under a ground fault because of an inadequate raceway EGC is something that the CODE requires you to consider too.

EGC's are present and bonded to the equipment, lighting protection, ground loop, VFD's have current protection in addition to motor control centers and fuses. Most of the installation was done professionally except for the control wiring where they got lost and I had to go in and rewire most of it. But I think a mistake was made in the flexible raceways I am not concerned with the other parts as no other concerns have been present. Even another company I asked as a professional favor looked over the pictures and agreed the LFMC was not of proper type. My problem is how can I prove this, when Installer doesn't want to waste weeks correcting and says no issue and so does designer.
 

rbalex

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And I think rbalex is stating that failure of an OCPD to open under a ground fault because of an inadequate raceway EGC is something that the CODE requires you to consider too.
Appreciate the support :thumbsup:

In addition, CMP14 is concerned about "objectionable (circulating) currents". [Section 250.6] Systems, driven from nonlinear sources, are particularly suspect. Even with bonding jumpers, raceways can and will carry some of the circulating currents. In such cases, the interlocking method for interlocked armors becomes critical. This is one reason MC-HL only permits corrugated armor.

Essentially, Division 2 doesn't permit equipment that arcs under "normal" design installation conditions. Unlisted interlocked armors have been shown to arc occasionally from circulating currents.
 

rbalex

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quote_icon.png
Originally Posted by DA72 ...
... An arc because a breakdown of improper insulation of raceway is my concern.
Why is that a concern? RMC/IMC isn't insulated at all. Most raceways aren't insulated. FWIW, LFMC isn't insulated either; it's jacketed.
 

DA72

Member
Location
Gibbstown NJ
Appreciate the support :thumbsup:

In addition, CMP14 is concerned about "objectionable (circulating) currents". [Section 250.6] Systems, driven from nonlinear sources, are particularly suspect. Even with bonding jumpers, raceways can and will carry some of the circulating currents. In such cases, the interlocking method for interlocked armors becomes critical. This is one reason MC-HL only permits corrugated armor.

Essentially, Division 2 doesn't permit equipment that arcs under "normal" design installation conditions. Unlisted interlocked armors have been shown to arc occasionally from circulating currents.

:thumbsup: Now were talking. The purpose of all 501 requirements is to keep flammable gases (or vapors) and ignition sources from reaching each other. In some cases, you may not have enough information to determine if a location is going to be Div. 2 or if you “have to” adhere to Div. 1 requirements. Don't think in terms of what you can get by with. Ask yourself how well you are keeping fuel and ignition apart. That's one question you never want forensics engineers to ask about something you designed or built. (see bold wording below)

For Div. 2 spaces, you can use these wiring methods [501.10(B)]:

General wiring, which consists of:

  • Wiring methods permitted in Class I, Div. 1 areas [501.10(A)].
  • Threaded rigid metal or intermediate metal conduit.
  • Enclosed gasketed busways and enclosed gasketed wireways.
  • Type PLTC cable per Article 725 (avoid tensile stress at the termination fittings).
  • Type ITC cable [727.4(3)].
  • Cables — MI, MC, MV, or TC — with termination fittings.
Flexible wiring. Where limited flexibility is necessary, you can use one or more of:

  • Flexible metal fittings
  • Flexible metal conduit with listed fittings
  • Liquidtight flexible metal conduit (or nonmetallic conduit) with listed fittings - (doesn't give reference to Article 350 which discusses types of LFMC to be used, which is how they are fighting how they installed was correct.)


 
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