ESD flooring in electrical room

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J-InTheJ-Box

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Got one for you guys. Is there any reason why I should argue against putting ESD flooring inside an electrical room with 480/277V and 208/120V panels present? I would gladly accept any NEC references and/or safety regulations to support the argument.
Reason why I am asking: Boss of cleanroom design firm is amazing at cleanroom design but is not well versed at basebuild and other engineering disciplines. I am the sole electrical person with two years experience so I want to find out if my reservations are right before arguing my position.
 
J-InTheJ-Box said:
Got one for you guys. Is there any reason why I should argue against putting ESD flooring inside an electrical room with 480/277V and 208/120V panels present? I would gladly accept any NEC references and/or safety regulations to support the argument.
Reason why I am asking: Boss of cleanroom design firm is amazing at cleanroom design but is not well versed at basebuild and other engineering disciplines. I am the sole electrical person with two years experience so I want to find out if my reservations are right before arguing my position.
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Why does your boss want to incur the extra expense of ESD flooring in the electrical room? What purpose does he think it serves, since there are no WIP carts or open cassettes likely to be floating around that space?
 
gadfly56 said:
Why does your boss want to incur the extra expense of ESD flooring in the electrical room?
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My thought, too, sort of like installing an ESD floor for the cafeteria or the loading dock. (I don't see any reason against it, other than needless expense.)

And if it's the usual bare concrete, unless the air is very dry it's probably conductive enough to avoid any ESD problems.
 
zbang said:
My thought, too, sort of like installing an ESD floor for the cafeteria or the loading dock. (I don't see any reason against it, other than needless expense.)

And if it's the usual bare concrete, unless the air is very dry it's probably conductive enough to avoid any ESD problems.
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If it's slab-on-grade with no moisture barrier, you are most likely correct.
 
gadfly56 said:
If it's slab-on-grade with no moisture barrier, you are most likely correct.
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Situation is this: Slab on grade, no moisture barrier. Electrical room is outside the cleanroom envelope and across a non-ESD tiled hallway. Since there is no reason for ESD sensitive devices to go into this electrical room and the cleanroom researchers will have no need to go in this room, I am arguing against having ESD flooring in there.
 
gadfly56 said:
Why does your boss want to incur the extra expense of ESD flooring in the electrical room? What purpose does he think it serves, since there are no WIP carts or open cassettes likely to be floating around that space?
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Can't reason out why Boss wants it done. But, I am going to argue against it for several reasons: the electrical room is outside the cleanroom envelope and across a hallway, this is a research environment, only maintenance staff and electricians will need to go into the electrical room.
 
J-InTheJ-Box said:
Can't reason out why Boss wants it done. But, I am going to argue against it for several reasons: the electrical room is outside the cleanroom envelope and across a hallway, this is a research environment, only maintenance staff and electricians will need to go into the electrical room.
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I'm with you, FWIW. If the space were part of a clean aisle or some such I might see the point. As you describe, it I can't see it.
 
J-InTheJ-Box said:
Glad to hear it. Point has been argued through email, respectfully, of course.
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If it means anything, I used to be a facility manager for a semiconductor tool manufacturer with about half a dozen clean rooms throughout the building. I'd have had the same opinion back then.
 
Did a little more digging becasue I was curious as we install a lot of this for the Army telecommunications infrastructure and there are always electrical panels in those spaces. The resistance of this stuff is extremely high. I would place a small bet that it is even a lot higher than wet concrete.

This is from product data for SDT by Armstrong.

Resistance:
ESD-S7.1 and ASTM F-150

Point to point and point to ground: 106 to 109 ohms
 
luckylerado said:
Did a little more digging becasue I was curious as we install a lot of this for the Army telecommunications infrastructure and there are always electrical panels in those spaces. The resistance of this stuff is extremely high. I would place a small bet that it is even a lot higher than wet concrete.

This is from product data for SDT by Armstrong.

Resistance:
ESD-S7.1 and ASTM F-150

Point to point and point to ground: 106 to 109 ohms
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Numbers check out. I have 10 distribution panels spread throughout the CR space, which will have ESD flooring all throughout. I dont have a problem there. The issue being raised is in the separate, dedicated electrical room where the CR users have no business going in, only maintenance personnel and electricians. To access the electrical room, you have to walk down a hallway that runs next to the CR before entering the electrical room through a set of double doors.

I think we've established that safety won't be an issue here. The current flowing through you would be measured in micro to nanoamps if you were to come into contact with any energized or live parts in a line to ground situation. In a line to line situation, you'd probably end up dead or missing limbs. So, that leaves cost as the only remaining issue.
 
Well other than you would be a so much better conductor with the ESD matting, which is meant to attract electrical discharge.....He does realize that there is copper run under that matting?
 
cowboyjwc said:
Well other than you would be a so much better conductor with the ESD matting, which is meant to attract electrical discharge.....He does realize that there is copper run under that matting?
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A high resistance conductor between 100k ohms and 100M ohms... In the stack exchange forum, one commenter mentioned that the typical ESD flooring goes up to 250V before you exceed the voltage rating of the resister. I suppose that alone would put safety back onto the table as an issue.

I'm getting valid points from everybody here and its helping to discuss this topic as a new point of view lets you look at a problem differently.
 
cowboyjwc said:
Well other than you would be a so much better conductor with the ESD matting, which is meant to attract electrical discharge.....He does realize that there is copper run under that matting?
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Im sorry but I strongly disagree with everything that you said. Not at all true. You are no more conductive and nothing is going to suck electricity towards it. SDT just gives a path to earth for static discharge only caused by friction in a low humidity environment seperated from earth by an insulator typically on your feet. Would not even blow a breaker if you laid a live conductor on it.
 
luckylerado said:
Im sorry but I strongly disagree with everything that you said. Not at all true. You are no more conductive and nothing is going to suck electricity towards it. SDT just gives a path to earth for static discharge only caused by friction in a low humidity environment seperated from earth by an insulator typically on your feet. Would not even blow a breaker if you laid a live conductor on it.
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Likely true, the other concern was cost for something that wasn't needed in the first place. Concrete is likely already going to be there, anything else applied to it is more cost.
 
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