Panel in Wet Location 1

[timm333]

We are installing a distribution panel in a building. The building has sprinklers. So a weatherproof (Nema 3R) panel will be required. The problem is that it can be dangerous in case the sprinklers go off at the same time when someone is performing maintenance at the panel.

If we put a warning label on the panel, something like this "disable the sprinklers before opening the door".

Will this warning label satisfy the NEC code?

 

[dpc]

First of all, NEMA 3R is raintight, not waterproof. So I would put in a NEMA 4 panel if I was concerned about water damage. This is generally never done in my experience.

Secondly, are we talking fire protection sprinkler system? There is no way a fire marshall would allow the sprinklers to be manually disabled in order to access an electrical panel. If the sprinkler system activates, this panel will be the least of your problems.



David Castor

http://www.cvoes.com

 

[timm333]

Yes these are fire protection sprinkler.

Is it allowed by the code to put a Nema-4 panel in a building that has fire protection sprinklers?

 

[dpc]

Sure, you can a NEMA 4 panel indoors - it's not a Code issue. But what about everything else that would get wet?

David Castor

http://www.cvoes.com

 

[timm333]

Dpc, you are right; other equipment like lighting fixtures, speakers, security cameras, and smoke detectors will also be wet if the sprinklers go off.

And it can be dangerous if someone is working on this equipment at the same time when the sprinklers go off.

What should be the solution to this problem?

 

[rasevskii]

Do a Wiki search on sprinkler systems. Only those sprinkler heads at the point of an actual fire will have their thermal elements triggered, releasing the water at the point of the fire only. Unless it is a deluge system whereby a large group of sprinklers will be activated centrally at the same time.

If there is actually a fire, no one will be concerned about water damage to electrical panels or anything else in the space. Priority is putting out the fire and preventing a larger fire. What was ruined by the water would have been more ruined by a fire, if not the whole property, if there were no sprinklers.

As dpc says, no way will you be allowed to disable the fire protection just to work inside a panel.

rasevskii

 

[timm333]

The main issue is not damage to equipment. The issue is just the safety of the person working on panel.

I just want to confirm that installing Nema-4 electrical equipment (like panels, light fixtures, etc), in a building having sprinklers, is not a violation of code.

Please confirm...

 

[dpc]

No, NEMA 4 enclosures indoors are not a code violation. It's done all the time in areas subject to washdown.

David Castor

http://www.cvoes.com

 

[waross]

If it is hot enough to trigger a sprinkler it will be too hot to work. Smoke and flames will also be a strong indicator that the premises should be vacated. If you are working under a dry system and break a sprinkler head, the escaping air will give you enough time to vacate.
Deluge systems are generally used for area protection of refineries and similar high risk areas. Some enclosed parking areas may also use a deluge system.
Still, if you are in an area protected by a deluge system you will probably be alerted by the sight of flames and smoke. If conditions warrant a deluge system you may also need hazardous classified electrical equipment.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[davidbeach]

If you're in an area with a deluge system, it is also really easy to dump the electrical system before the water arrives. I've never seen any difference in the equipment used in sprinklered building and non-sprinklered buildings.