# Class 1, Div. 2 Septic System



## Woman on the job. (Nov 4, 2015)

I hope someone can help. I'm wiring a septic system for a winery (I've done one other ). I did it in 3/4" pvc. When the inspector came out, he said he'd have to assume it was a class 1 div. 1 system since an engineer hadn't put his stamp on it. The facility has floor drains. An engineer finally stamped it as class 1 div.2 - since dumping petrol down the drains wouldn't be part of normal operations. There are three risers. My question is do I have to go rigid with explosion proof box and seal off all the way to the control boxes? I've read that you need a seal off when you leave the classified area, but that would make it just outside each riser and seal offs can't be buried. Are there any other options? Can I keep any part of the pvc system? Thanks


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## sbrn33 (Mar 15, 2007)

Can't say I have ever ran into that in a septic system. how would that end up Class 1 Div 1


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## Black Dog (Oct 16, 2011)

Woman on the job. said:


> I hope someone can help. I'm wiring a septic system for a winery (I've done one other ). I did it in 3/4" pvc. When the inspector came out, he said he'd have to assume it was a class 1 div. 1 system since an engineer hadn't put his stamp on it. The facility has floor drains. An engineer finally stamped it as class 1 div.2 - since dumping petrol down the drains wouldn't be part of normal operations. There are three risers. My question is do I have to go rigid with explosion proof box and seal off all the way to the control boxes? I've read that you need a seal off when you leave the classified area, but that would make it just outside each riser and seal offs can't be buried. Are there any other options? Can I keep any part of the pvc system? Thanks


It's going to need to be sealed off somehow.


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## glen1971 (Oct 10, 2012)

Woman on the job. said:


> I hope someone can help. I'm wiring a septic system for a winery (I've done one other ). I did it in 3/4" pvc. When the inspector came out, he said he'd have to assume it was a class 1 div. 1 system since an engineer hadn't put his stamp on it. The facility has floor drains. An engineer finally stamped it as class 1 div.2 - since dumping petrol down the drains wouldn't be part of normal operations. There are three risers. My question is do I have to go rigid with explosion proof box and seal off all the way to the control boxes? I've read that you need a seal off when you leave the classified area, but that would make it just outside each riser and seal offs can't be buried. Are there any other options? Can I keep any part of the pvc system? Thanks


I'm pretty sure you'll need seals when leaving the Div 2 area and into any panels requiring seals (relay panels, switches with non factory sealed contacts, etc.).. Seals cannot be buried.. Can you go to a GUA fitting with a pour cover instead of an EYS on your area change seal?
The wiring method (conduit type) will have to be approved for the area.. Up this way, PVC is not approved in Class 1 Div 2 areas and you would have to be in rigid, either aluminum or GRS...


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## 360max (Jun 10, 2011)

501.10(b)


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## Woman on the job. (Nov 4, 2015)

If an engineer has not stamped what the systems classification is - the inspector assumes it's class 1 div.1


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## backstay (Feb 3, 2011)

If you have an explosive environment in your septic system, something's wrong.


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## Woman on the job. (Nov 4, 2015)

Ha! Thanks for your code note. I'm reading it over and over. It's starting to make a little more sense.


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## Woman on the job. (Nov 4, 2015)

This is to "backstay". The classification is because of the floor drains in the building. Something flammable could be dumped.


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## backstay (Feb 3, 2011)

Woman on the job. said:


> This is to "backstay". The classification is because of the floor drains in the building. Something flammable could be dumped.


Ok, that's a different story.


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## hardworkingstiff (Jan 22, 2007)

Woman on the job. said:


> This is to "backstay". The classification is because of the floor drains in the building. Something flammable could be dumped.


Are flammable liquids being used in the winery where these floor drains are located, or is the AHJ just saying someone might walk in carrying a flammable liquid and then dump it down the drain?

I've only wired a couple of septic lift pumps (I'm assuming this is what you are describing). I did not have to install sealoffs.

The thing you do not want to do is to cut the cords to the pump motors or float switches. They are left long so that you can run them through a conduit to the controller located adjacent to the tank (above any classified location, due to the sewer gases). I was allowed to duct seal both side of the PVC and that was adequate.

Explain the the inspector that a pump or float switch that needs to be replaced will wind up having a cord cut and an non explosion proof connection made because the sealoff sealant would not allow the old cord to be pulled out and the newer cord to be pulled in. 

In one discussion I had about this, we thought it would be code compliant to let the pvc stub up out of the ground but stay below the top of classified location (leaving the conduit in the classified location so it never leaves the classified location .. no seals required). The cord is most likely listed to be in this classified location and you just need to use the "proper" (whatever that is) cord grip in the bottom of the controller. 

The whole idea is to not having any connections other than in the control cabinet and in the float switch or pump.


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## Woman on the job. (Nov 4, 2015)

Thanks for all the info. Good argument . The only flammable liquid at the winery is what goes into the forklift.


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## MTW (Aug 28, 2013)

I've never seen a septic system wired as a classified location.


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## Mulder (Sep 11, 2010)

backstay said:


> if you have an explosive environment in your septic system, something's wrong with your diet.


fify


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