When are Sprinklers Omitted in Electrical Rooms?

7/17/2019

It is a popular and well-established concept that water and electricity don’t mix.

Water is electrically conductive which creates a major hazard of electrocution where a continuous pool of water meets a live electrical feed.

Can We Omit Sprinklers in Electrical Rooms?
On a few occasions I have come across building authorities and building owners who assume that sprinklers will not be installed inside traditional electrical rooms.

Why? The basic tenant that water and electricity don’t mix.

While the concept is important, the intent of sprinkler protection throughout a building is not just for each item within a building, but the building itself.

The primary intent of sprinklers is suppression – or stated differently – to prevent the growth of fire from the room of origin throughout a building. This includes all the rooms and spaces beyond just the electrical room where a fire could begin.

This week I’m digging into guidance surrounding electrical rooms.

NFPA 13 Guidance
NFPA 13 (2002 Section 8.14.10.3, 2007-10 8.15.10.3, 2013 8.15.11.3, 2016 8.15.11.2, 2019 9.2.6) allows sprinklers to be omitted in electrical rooms, but only where each of the following are met:

The room is dedicated to electrical equipment only.
Only dry-type or liquid-type with listed K-class fluid electrical equipment is used.
Equipment is installed in a 2-hour fire-rated enclosure including protection for penetrations.
Storage is not permitted in the room.

Concerns with Providing Sprinklers in Electrical Rooms
Providing sprinklers within electrical rooms could:

Risk safety for responding firefighters in or near electrical rooms where water could discharge over live equipment
Water could cause additional damage to electrical equipment

Historical Approach
Prior to the 1994 edition of NFPA 13, important electrical equipment were required to have hoods (or shields) comprised of non-combustible construction to prevent direct contact by sprinkler discharge. All electrical rooms were required to be sprinkler protected.

Beginning with the 1994 edition, NFPA 13 introduced language to address concerns for firefighter safety and equipment damage. Sprinklers could be omitted in electrical rooms where the room contains dry-type equipment (no oils), is dedicated to electrical equipment only, is fire-resistant to reduce fire spread, and the room has no storage hazard.

The 2016 Edition, the requirement for equipment hoods or shields was removed to direct it under the scope of NFPA 70.
Just recently for the 2019 Edition new text was introduced such that no storage is permitted (non-combustible storage had been allowed) and liquid-type K-class (less flammable, non-spreading fluids) would be allowed.

International Building Code Input
The International Building Code (IBC) does not allow the omission of sprinklers “merely because it is damp, of fire-resistance-rated construction, or contains electrical equipment” (IBC 2000-18 9.3.1.1.1).

Within the same code section, the IBC does allow sprinklers to be omitted in “generator and transformer rooms separated from the remainder of the building by walls and floor/ceiling or roof/ceiling assemblies having a fire-resistance rating of not less than 2 hours.” These rooms must have an approved automatic fire detection system.

According to IBC commentary, buildings with sprinklers omitted in one of the sections allowed by the IBC would still be considered fully-sprinklered throughout and in compliance with the code and NFPA 13. This distinction is important as it carries eligibility for code alternatives, exceptions and reductions.

Today’s Consensus
Combined, both the IBC and NFPA 13 require electrical rooms to be protected unless the prescriptive alternative option is followed.

As NFPA 13 commentary outlines, sprinkler systems have been successfully installed in rooms containing electrical equipment for over 100 years with no documented instances of a problem. While still seemingly controversial, most projects designed today include sprinkler-protected electrical rooms.

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14 Comments

Mike

7/18/2019 08:31:40 am

Great synopsis Joe,

We run into this issue daily as we renovate floors. An existing electric room does not have a rated door or penetration, so we call for sprinklers to be installed. The AHJ signs off on the sprinkler only to have the electrical inspector request the sprinkler to be removed for safety reasons.

If sprinkler heads are required, we typically specify a side wall heads to limit water-filled piping in the room.

Another word of caution, NFPA-70 does not permit any "foreign" piping to be installed in the dedicated space above the electrical panels/equipment. Dedicated space is defined as the area up to 6 feet directly above the outline of the panels. Sprinkler piping cannot be in this zone at all.

We also follow the same guideline for IT/Server Closets as most client IT personnel don't want water anywhere near their server racks.

Derrick Shaver

7/20/2019 08:23:56 am

Since most clients don't want water in their IT server rooms, wouldn't a clean agent be more effective in this situation?

I've been tasked with coming up with the requirements for an Engineering office that is fully sprinklered. The building is 3 stories tall and the server room is on the first floor (above grade). The engineering firm is having a hard time believing sprinklers go in their server room. The facility is in Knox County, TN which has adopted the 2018 IBC.

What would be the requirements, and is there any exceptions they can take without "breaking the bank"?

I would appreciate any help or direction.

Ben O'Regan

7/21/2019 02:55:55 am

The companies that sell clean agent systems have done a great job convincing people that clean agent is ideal for computer server rooms. The reason for upselling customers on clean agent systems is very simple - that's where the big contractors make their money. The market for sprinklers is very competitive with so many little contractors competing with the big ones, but clean agent systems always have a healthy profit margin.

If you don't want to install sprinklers in server rooms, you will need an exemption from full sprinkler coverage from your AHJ as IT rooms are not a permitted exception under NFPA 13 rules.

You also need to fire rate the room, fire stop any penetrations, install a fire door, install fire dampers on any ventilation equipment, install the clean agent system and interface it with the HVAC system. Then there will be costs associated with ongoing maintenance and inspections and costs associated with disposing of the agent in an environmentally responsible way when it comes time to decommission the system.

Pre-action sprinklers are a much cheaper solution that avoids the perceived risk of having a water leak or unwanted discharge damage equipment.

NFPA 75 advises sprinklers are good fire protection for computer rooms, partly because of the high reliability of these systems (unwanted discharges are statistically very rare) and computer equipment will often survive water exposure. It goes on to say, if you want an clean agent system, you should do a cost benefit study first, presumably because it's going to be a lot of money and the benefit will be difficult to justify.

Derrick

7/21/2019 10:15:10 am

Wow...thanks Ben...very good information

7/22/2019 03:19:55 am

You are very welcome Derrick. I think it's good to have discussions like this online.

Unfortunately, a lot of people consider themselves experts because they have listened to sales pitches from vendors selling one technology or another. Perhaps your client is in this situation, then you probably want to take the attitude that the customer is always right.

JOE MEYER

7/22/2019 07:38:53 am

Ben,

I can't speak to the sales side of the industry, but the one major benefit that clean agent systems provide which pre-action systems do not is the ability to extinguish a fire without damaging equipment.

For data centers or larger server rooms the loss from equipment damage or even just downtime is so large that the clean agent systems are well worth it to some building owners. These data centers and large server rooms are very different from a basic electrical room though - and the root of the solution (in my opinion) just stems from quality conversations with building owners. Clean agent doesn't come cheap!

7/22/2019 07:33:12 am

Just to be clear, this article isn't addressing server rooms with alternative protection, but rather just basic electrical rooms.

Clean agent can be a great solution when damage to equipment or downtime is unacceptable to an owner. Typically this isn't the case for basic electrical rooms but it could be the case for server or high-value equipment rooms.

7/22/2019 08:39:30 am

Hi Joe, Great Blog!!

We got a little sidetracked talking about computer server rooms.
I think it's good to make the distinction though as some people assume that computer rooms should be handled the same as electrical plant rooms. It's worth pointing out that server rooms are not automatically exempt from having sprinklers because they don't meet the NFPA definitions of "electrical equipment rooms housing only dry electrical equipment". Server rooms are not automatically exempt from having sprinklers. If the building requires sprinklers, you need an exemption from the local authority to omit them from server rooms.

7/22/2019 08:42:33 am

Yes, you nailed it. Well said!

Scot Deal

7/26/2019 06:18:48 am

I am a bit confused as to why we hesistate to install wet-pipe sprinklers to protect electrical or computer rooms.... put another way... what part did we not understand about the above article where it wrote

" As NFPA 13 commentary outlines, sprinkler systems have been successfully installed in rooms containing electrical equipment for over 100 years with no documented instances of a problem. While still seemingly controversial, most projects designed today include sprinkler-protected electrical rooms "

If you are considering a "clean agent" instead of sprinklers, consider that for a 800 sq. ft electrical room that is 13 ft high, the FM-200 will cost about $130,000; extending sprinkler coverage will cost about $3,000. The $130k includes a second shot (which you will probably [Pb>0.6] need), but does not include maintenance (which you also will probably (Pb > 0.9) need.

Here is a paper on how FM-200 is dirtier and more toxic than water, how FM-200 is more expensive by orders of magnitude), and how FM-200 is far, far, far less reliable than water-filled sprinklers.

https://tinyurl.com/Green-vs-Dirty-Clean-Agent

The USA military has 4 branches and 4,000+ installations planet-wide. They keep statistics (but don't share them); But, since 2001, wet-pipe sprinklers have been required over USA milititary electrical equipment and computer rooms. This would have been revoked were it ineffective. The proof is in the pudding. For many reasons, fire protection of electrical and electronics (computer server rooms) is better, far better with simple wet-pipe sprinkler.

It must be EMPHASIZED, THAT PRE-ACTION is not simple, nor it is BETTER than wet-pipe sprinkler. Pre-action sprinkler systems have a dismal, DISMAL reliability record. If you want to use statistics, use them on pre-action sprinklers. It is better to go naked with no active fire protection, than to go with the pre-action sprinkler or dirty "clean" agent. Because if you pay for either of those two options, there is a 66-75% chance you will be operating naked in 7-years from acceptance testing...this is because both of these systems are statistically likely to be impaired. Just keep it simple, wet-pipe (not pre-action) sprinklers... or you most likely will end up naked for automatic fire protection--even if you paid for 'bling-bling' fire supression. Note, going naked with automaitic fire protection in computer server rooms IS A TOLERABLE risk in 24/7 operations. This is because you have: 1) human intervention and 2). the likelihood of fire in these occupancies is acceptably low (both NFPA 2001 and FM Global say so).

Regarding electrical shock hazard to fire fighters... it is possible, but highly unlikely. In 1992 Verlo reported on salt-water and fresh water, AC and DC current with water. His article [1992, Cables and Fire Protection -Conference Proceedings, London] shows the hazard from electrical shcok to firefighters is absurdly exaggerated. Just aks for the article and you shall receive.

Scot Deal PE/FPE
Excelsior Risk & Fire Engineering
(Eurekaignem at gmail dot com)

Doug White

7/24/2019 05:52:51 pm

Joe,

Your blog always gets me asking questions and then quickly answers them. Thank you for that.

In Australia, our local AHJs will often mandate removal of sprinklers from electrical rooms, however it is not code compliant. A Fire Engineered solution is required with fire falls and doors etc as per NFPA13.

This is considered safety for personnel that may be in the room, not just fire fighters.

It always creates an interesting argument.

7/25/2019 12:29:24 am

Hi Doug,

I'm skeptical that having water in an electrical room constitutes a serious hazard as all live conductors are all either double insulated or housed in grounded metal cabinets.

You can't get a shock just by standing in a pool of water - the current travels directly to ground, in the case of a grounded metal cabinet, voltages can't get out of the cabinet.

Some unlikely events would need to occur before someone got a shock. Maybe if a cable were to burn through its insulation and contact someone who was standing on a wet floor, or if a cabinet with live equipment was left open and someone contacted it while standing on a wet floor.

There must be millions of this type of installation in the US, and no reported incidents of electric shock from fire fighting water. The evidence is in the statistics.

Jeff Yuill

1/8/2020 10:47:56 am

I would suggest that most electrical rooms do not have enough combustible loading within to set a sprinkler head off in the event of a fire involving the cable coating (XLPE) or some other combustible compoenent of the switchgear.

Due to the unattended nature of these spaces and slow building fires that are typical, I would suggest that smoke detection is the prefered method of protecting these spaces.

James

1/8/2020 02:14:29 pm

Jeff - if we're talking a smoldering fire with a cable or series of cables - sure. Those won't activate a sprinkler in any type of room until it grows large enough that the ceiling temperature is 150+ deg F.

Electrical room fires happen all the time, and there's plenty of combustible (arcing and potentially explosive) equipment that would benefit from the cooling effect of sprinkler suppression.

That being said, smoke detectors and sprinklers achieve two different things. A smoke detector is great for electrical rooms in that they can raise alarm and get early attention to a fire when it could be manually extinguished. A detector in it self has no "protection" from a fire, however. A sprinkler protects the room and surrounding spaces from large fire growth and spread.

When are Sprinklers Omitted in Electrical Rooms?

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