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Discussion Starter · #1 ·
Hey everyone,

I've never done any explosion proof work, and this facility I'm going to wire next week has some wiring that will be done after with Rigid conduit, but I want to get and understanding of it ahead of time.

I know a little bit of what's required for this, but I'd like some input. Inside the bubble, there will be 2 cameras, 2 motion sensors, 2 keypads, 2 door contacts, and 2 door strikes. We are sourcing the explosion proof items, but I'm not sure what I need to do when it comes to the conduit. I know I'll need seals filled with Chico, but will I need it on both ends?

Any input on this would be helpful.

@Navyguy is this something you could help us out with? I know you're not far from Niagara.

Rectangle Font Parallel Schematic Plan
 

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Discussion Starter · #3 ·
You have to seal when you change classification and all sparking devices
So I need one right above the boxes with the devices, then one on the other end of the conduit once I leave the classified area? so essentially 2 per conduit right?
 

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Are you installing the rigid or is the prime EC?
 

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Discussion Starter · #7 ·
You need a seal installed directly at every sparking device, that is not factory sealed and listed that way. Not just above a junction box.
The runs to the IT area are so short that they will all be home runs (the IT room is directly to the left of the bubble area).

So if I install a box on the wall for the keypad, I need a seal right above it, then a seal on the far end of the conduit. That makes sense.

Now how about my camera? I can't hard pipe it in. I need a flexible connection to it, so how would that work? Metallic liquid tite flex with the rated connectors?

Are you installing the rigid or is the prime EC?
We're not sure yet, as that area of the building hasn't been quoted yet because it's so up in the air. I have no issues installing it as long as I know 100% what is needed. I know I need seals, I just don't know where. We may end up getting the EC, we are not sure yet as it will all be surface at the finishing stage.
 

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Liquid tite doesn't have explosion proof certification. Your intrinsically safe camera may come with an approved cable.
Your seal is immediately after the conduit leaves the area (ie no threads between the classified area and the seal - coupling, box)
Save yourself a crap ton of grief and let the prime EC do the rigid and pouring of the seals
 

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So if I install a box on the wall for the keypad, I need a seal right above it, then a seal on the far end of the conduit. That makes sense.

Now how about my camera? I can't hard pipe it in. I need a flexible connection to it, so how would that work? Metallic liquid tite flex with the rated connectors?
have you looked into INTRINSICALLY SAFE devices. they are built so that they are not an explosion hazard. Low voltage and very low short circuit amps from a separate power supply, presumably out of the zone; also the wiring out of the power supply would be intrinsically safe. but you still have to seal conduits when you cross a zone border to prevent air/vapor travel out of the zone.

as wcord said let the EC run pipe and seals .... unless you have practiced before and are good at it or just want to do it
 

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I can't speak to Canadian standards, but in the US the first thing that needs to be determined is the area classification. Is it Class I Div I, Class I Div II, a mixture of both or something else? Without that information the job cannot be planned, designed and priced.

Hazardous materials contained, stored and how they are used all have an effect on the classification of the room and the area outside the room. The ventilation system, how it is sized, designed and controlled are also factors in how the area is classified.

This should be done by a professional engineer and documented before you can begin selecting equipment and wiring methods, unless your going to accept all of the future liability.
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Next up would be is your equipment selected and listed for the location. Only then can you begin to select conduit and wiring materials and methods.


Here in the US, LTFMC can be used in CL I DIV II locations with approved conduit and fittings, your codes may differ.
 

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I see a lot of ACIC cable for instrumentation and I/T in classified areas. There are lots of varieties of different conductor quantities, gauges, twists, shielding, etc.. The wholesaler usually has a few spools of different conductor configurations handy. You usually need to make due with whatever is on the rack. Getting obscure ACIC cabling from the catalog gets pricey and takes forever.

TECK90 for most power and fire alarm. I'm not very versed in the trade lingo but people I talk to mention JBs with built-in seals. Maybe your wholesaler may know more.
 

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Now how about my camera? I can't hard pipe it in. I need a flexible connection to it, so how would that work? Metallic liquid tite flex with the rated connectors?
Is the camera otherwise explosion proof? If not you need an explosion proof enclosure. If yes (or with the enclosure) then I've always used teck with explosion proof fittings. You can get teck with most common LV cables inside. (I've, uh, seen examples where a chunk of outer jacket and armour from a regular old 12c3 has been used as a raceway for LV/data with explosion proof connectors at each end. Obviously not a listed use.)
 

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So I need one right above the boxes with the devices, then one on the other end of the conduit once I leave the classified area? so essentially 2 per conduit right?
I would check the drawings and specs.

After that, like someone else mentioned, I sure would try to get intrinsically safe devices that operate on intrinsically safe circuits. That would make it so much easier.

What do the specs call for?
 

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Discussion Starter · #15 ·
What do these drawings show/call for?
View attachment 162011
I would check the drawings and specs.

After that, like someone else mentioned, I sure would try to get intrinsically safe devices that operate on intrinsically safe circuits. That would make it so much easier.

What do the specs call for?
There's currently nothing about it because it's a bubble my boss added for info about it.

We haven't been told anything about it right now except "it's class 1 div 1 and class 1 div 2"

I think we're just gonna go with hazardous location data cable for everything. We are using a pneumatic strike for the door.
 

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Well, I just realized this is CEC ( :) ) so I cannot comment about what's required. But I do have a "watch out for" since you say you have never done this type of conduit work.

I've been behind more than one electrician that wired up a pump on top of a gas tank that did not have a union or conduit disconnecting means between the sealoff and the pump. Pump JB, GRS nipple into the top of the sealoff, union on the bottom of the sealoff to attach the conduit. Once the sealoff is poured there is no way to disconnect the pump to change it out where if the union was between the sealoff and the pump JB.

Good luck with this, just think and you will do great. :) (easy for me to say)
 

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Discussion Starter · #17 ·
Good luck with this, just think and you will do great. :) (easy for me to say)
Yeah I was thinking about unions.

Thank you for your kind words 😁

Again, this is all in the planning stages for a couple of months down the road. Even if I don't do it, I'd still like to understand what's required.
 

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There's currently nothing about it because it's a bubble my boss added for info about it.

We haven't been told anything about it right now except "it's class 1 div 1 and class 1 div 2"

I think we're just gonna go with hazardous location data cable for everything. We are using a pneumatic strike for the door.
There needs to be clarification between what is Zone 1 (Cl 1 Div 1) and what is Zone 2 (Cl 1 Div 2) long before you get started. Pipe fittings change- GUA versus gasketed condulet. Flexible conduit differs from costly x-proof flex to liquid tight. Teck connectors, if used, differ from only STX to ST/STE and STX.
What is the process that is moving it to a hazardous location?
 

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Does Canada allow Aluminum rigid conduit in hazardous locations? It is much easier to cut, bend, thread.
Yup. That was all I mainly installed in hazardous locations. Used GRS in a strand board plant and a small handful of sweet gas sites. We gradually phased out stocking large amounts of steel pipe or fittings, unless spec'd.
 
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