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Electrical rooms and sprinkler systems

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rrewis

Mechanical
Dec 19, 2006
37
I searched the archives but could not find what I'm looking for. I need the code number and section number that relates to sprinkler system piping running through electric rooms containing equiptment of less than 600 volts. Would someone please point me in the right direction?

Thanks,
Russell Rewis
 
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Any building that has equipment with more than 240 V power should be considered dangerous if it has a sprinkler system that can go off and cause electrocution. Fire Marshals love to require sprinkler systems. If you ask them to put in writing that they will assume any liabilities if the fire suppression system goes off and causes electrocution, suffocation, or pollution, most will not.
If state or federal safety laws do not allow water to be used by employees to put out electrical or petroleum fires, the Fire Marshal cannot enforce a sprinkler system if the equipment is electrical or contains petroleum products.
 
In Western Canada, sprinkler systems have been used in electrical rooms for decades.
26-008 Sprinklered Equipment (See Appendix B).
Where electrical equipment vaults or electrical equipment rooms are sprinklered, the electrical equipment contained in such vaults or rooms shall be protected where needed by noncombustible hoods or shields so arranged as to minimize interference with the sprinkler protection.
Appendix B gives advice for avoiding a direct stream of water on live parts.
Yes, there was initial resistance by the electrical community to sprinklers over electrical switchgear but we learned to live with it.
respectfully
 
I agree with you EdDanzer, I don't see the need nor the practicality for sprinklers in such rooms. Their walls are fire rated anyway.

Waross, We go by the same code wording as you do there in Canada.

But my question is not the requiremnt, but when systems are installed is there any code that you can quote that prohibits running the piping completely through the room?

Russell
 
Do I understand that you are not objecting to the sprinkler head, but are objecting to the passage of a large diameter sprinkler supply line through an electrical equipment space?
I do not know of any such restriction in the electrical codes.
I would try the mechanical forums, or the mechanical code forums.
respectfully
 
waross,
Not exactly, you see I'm the one that's gonna run the pipe through the room. I'm a fire sprinkler contractor, so I thought I'd ask the electrical experts.
 
Make sure piping does not restrict access to the electrical equipment. Minimum clear space requirements can be found in the NEC.
 
In general, NEC Article 110 does not allow the presence of "foreign" piping or equipment in the space above electrical equipment. So if the piping is not part of a sprinkler line that is serving the electrical room, I do not think you are allowed to run the piping through the room, subject to a few exceptions in Article 110.

There may be some exemption for fire water piping, but I'm not aware of it, and a cursory review of Article 110 didn't turn one up.

But I'm not really a fire protection guy.
 
From 110.26

(b) Foreign Systems. The area above the dedicated space required by 110.26(F)(1)(a) shall be permitted to contain foreign systems, provided protection is installed to avoid damage to the electrical equipment from condensation, leaks, or breaks in such foreign systems.

The dedicated space is the clear space requirement I mentioned above where nothing is allowed.
 
If you are outside of the required work spaces and the dedicated equipment space, then you can run the fire protection pipe through the room. If you are above the dedicated space, a drip pan will be required. Many such rooms are protected by fire sprinklers. 110.26(F)(1)(c) specifically permits sprinkler protection of the dedicated space.
(c) Sprinkler Protection. Sprinkler protection shall be permitted for the dedicated space where the piping complies with this section.
Actually the only way to extinguish an electrical fire is to stop the flow of current. After the current flow has stopped you are left with a Class A fire or as a number people in the fire service like to call it a solid Class B fire.
Don
 
Read the applicable NFPA standards.

NFPA 13
8.15.10.1 Unless the requirements of 8.15.10.3 are met, sprinkler protection shall be required in electrical equipment rooms.
8.15.10.3 Sprinklers shall not be required in electrical equipment rooms where all of the following conditions are met:
(1) The room is dedicated to electrical equipment only.
(2) Only dry-type electrical equipment is used.
(3) Equipment is installed in a 2-hour fire-rated enclosure including protection for penetrations.
(4) No combustible storage is permitted to be stored in the room.

NFPA 15
1.3.2 Water spray protection is acceptable for the protection of hazards involving each of the following groups:
(2) Electrical hazards such as transformers, oil switches, motors, cable trays, and cable runs

Table 6.1.2.2 Electrical Clearance from Water Spray Equipment to Live Uninsulated Electrical Components

...

 
Thanks for leading me to the NEC and the section concerning my question. That gives to me the answer I need.

Thanks to all for taking the time to share your knowledge.
Another great forum,

Russell
 
You should be aware of potential pollution liabilities of extinguishing any fire with water. No regulation can force a person to accept a greater liability than it eliminates. When electrical items burn, they generate some very bad things to have flow into a creek or river. Remember there is a cradle to grave liability and no statue of limitations on pollution spills.
 
EdDanzer,

Whether a sprinkler system is installed in an electrical room or not is not a decision made by the sprinkler contractor. As with most all construction projects there are several engineers, including electrical engineers, state and local authorites and insurance providers, for the various trades that are making those calls. The trades, such as myself, have to follow their requirements and only make suggestions. Sprinklers contractors would not require such an arrangement.
 
Ed,
You should be aware of potential pollution liabilities of extinguishing any fire with water. When electrical items burn, they generate some very bad things to have flow into a creek or river.
While that is very true, a large number of other building construction produts, finishes and furnishings have the same issues with polution, and they exist in the building in far greater volumes than those that are a part of the electrical system. These other products will become involved in the fire if the fire is not confined to the electrical room. Water is the only reasonably available and effective extinguishment agent for most fires. Are you suggesting that those of us in the fire service should stand back and watch the building burn down because of the runoff from the use of hoselines? If the application of water by the sprinkler system confines the fire to the room of origin, then there will be much less total runoff as we will not have to use our large stream to extinguish the building fire. The smallest fire service hose line will operate at ~100 GPM, the largest hand line at 250-400 GPM and master steams at 1000 GPM and up, with a few in excess of 10,000 GPM. A number sprinkler heads would have to open to equal the flow rate of even the smallest fire service hose.
Don
 
What I’m saying is that there are many conflicting laws some have a greater penalties than others. In many cases it would be better to let a building burn than to spray water on it if you could be held liable. With the current sue happy environmental groups, any thing you do that causes a pollution problem can be far more expensive than letting it burn. You will find many insurance companies have clauses to limit there liability from pollution claims.
 
When a building is required to be fire sprinklered, the electrical equipment spaces are also required to be covered. We recently finished a hospital central utility plant and we had to have every room covered, even my generator and transfer switch room. We are generating at 12.47 kV and have a control and distribution switch board as well as several automatic transfer switches, and were still required to have the sprinklers cover the entire room. Meetings with the OSHPD fire marshall did not provide any form of relief from this requirement. It is a common occurance. Some engineers specify NEMA 3R enclosures in these locations, but that involves an added expense. I guess it would be the client's call as to wether the additional protection would be worth the cost.
 
The final decision as to relative merits of sprinklering versus not sprinklering is really up to the AHJ. You can appeal, but your liability is not really going to be the determining issue.

After the AHJ, you have to make your underwriter happy.

As the national codes stand now, sprinklers are required in certain situations, as bad an idea as it might seem.

If the concern is the water quality of the effluent of a sprinkler event, I would think there would be other portions of almost any building that would be a bigger concern than the electrical room. Not to mention the fact that there are electrical circuits and panelboards throughout the entire facility.

 
This is an issue that is quite common. A lot of large multi-national blue chip companies do have sprinklers in their electrical rooms. This is usually a requirement of their insurance company.

One method of ensuring that there are no accidental discharges is a pre-action sprinkler system. In this arrangement the sprinker pipe in the room is empty unless a valve is open. This valve is actuated by the fire alarm system.

 
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