Rolling fire storage racks of the sort seen in hospitals 1

How about sidewall heads?

Just a thought

do you need 18 inches when using a sidewall???



add more heads???


raise the ceiling around the heads so you get the 18 as long as you to not obstruc the spray pattern??
There cannot be duct covering the entire room

raise the cieling as much as possible and lower wher there is duct, and add heads as needed??

you are only talking two inches

I think sidewall sprinklers require the 18" as well.

The only straw I can find is 8.5.6.4.

8.5.6* Clearance to Storage.
8.5.6.4 A minimum clearance to storage of less than 18 in. (457 mm) between the top of storage and ceiling sprinkler deflectors shall be permitted where proven by successful large-scale fire tests for the particular hazard.

which I doubt this has happened but you never know until you ask.

The area in question is not a large area it measures about 10'x20' and the problem really isn't mine because someone else lowered the ceiling.

There was a recent article on the SFPE Fire Protection Engineeering Journal on this specific subject.

The best approach might be to use "extended coverage" heads which are approved for 400 sq. ft. BUT you should install the heads as close as the technical data sheets allow (I know of one manufacturer who allows minumum 8 ft. head spacing) for the given sprinkler. This approach provides sprinkler heads which have a much flatter umbrella and will be more effective given the <18 in. clearance. You could install 6 heads in your 10x20 room and be fairly certain any anticipated fire will be controlled. You might want to involve a FPE or get written approval from the AHJ since this is outside of normal NFPA standards.

They had some good info on this at NFPA annual meeting in Las Vegas this year. Do not know if this is the same info that Stookey is referring too. BUT the full scale tests done on this type of storage produced some interesting results. The sprinklers took more then 60 minutes to activate, densities of .70/1500 did not control a fire because of the shielding. The smoke detector activated within 60 seconds of the start of the fire. We now require smoke detection to a CS even if we have sprinkler protection.

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Fire Sprinklers Save Firefighters’ Lives Too!

Wait a minute. There must have been some other contributing factor if the sprinklers in the example referenced by LCREP required >60 minutes to operate. I assume the situation described by SD2 has a smooth flat ceiling and standard gypsum walls which create a standard size room (10x20). Given these parameters, the sprinklers will operate during the early stages of the fire incident. The only potential problem outlined by SD2 was <18 in. clearance. There are very few instances I can think of where a sprinkler system would be considered effective if the heads fail to operate in the first 60 minutes.

By the way.......I am a huge supporter of smoke detection for early notification even when adequate water based fire protection systems are provided. Some hazards warrant both sprinklers and smoke detection.

The problem is in a very tight configuration the fire is very slow moving and not producing huge amounts of heat, thus the slow activation of the sprinkler. BUT once it does get going with little space for water to get to the seat of the fire, the sprinklers had little effect in controlling the fire. The key was early detection with manual firefighting.

NOW do not get me wrong, I am not saying you can eliminate the sprinklers, I am just saying in this case the fire detection played a large roll in the eventual extinguishment of the fire.

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Fire Sprinklers Save Firefighters’ Lives Too!

Short of any applicable test criteria that you may convince the AHJ to accept as a variance, or by using the equivalency clause, it seems to me that when owners insist on this arrangement, then we as installers have limited choices.

You need an independent detection system tied to you water based protection. Can you say Pre-action?

There is always a cause/effect relationship to owner's decisions. This one seems simple to me, you did not choose to use the compact/track shelving, the owner did.

The next best option is likely pre-action or perhaps gaseous based protection in combination with pre-action. Why try to suggest other methods such as extended coverage heads, or sidewalls, when this would clearly be outside their product listing? Do you really want that liability?

Using a pre-action system makes no sense at all. We are already dealing with a wet sprinkler system.......using a pre-action system would only reduce the overall reliability of the system (the actuation devices for the preaction system would have to operate prior to the introduction of water to the system).

Gaseous systems are also not a very wise approach because we are dealing with ordinary combustible materials (seated fires). Most gaseous systems are not designed or applicable for ordinary combustible materials; they are not considered an effective extinguishing agent for ordinary combustibles and the fire usually re-ignites after the concentration of the gaseous extinguishing agent dissipates.

As a FPE, we must understand that NFPA codes do not cover every possible scenario. In some instances we are required to use our experience and engineering judgement to develop designs which will be effective for the given occupancy/situation when the applicable codes/standards and product listings do not specifically fit a certain situation. Taking into acount the relatively small size (200 sq. ft.) of the room, understanding the reasoning behind the 18 in. clearance requirement and then doing a little research and math using the proven/tested umbrella pattern for a specific sprinkler head to confirm the water spray will not be obstructed is a solid engineering approach. I would also like to see smoke detection in this room for prompt manual response.

I would need to confirm several facts prior to writing a letter for this project, but I still maintain this approach is probably the best (and most economical) solution given the information included in the above posts by SD2.

Yes I agree pre-action system is a waste of $$ for a 200 sq. ft. room. IF the client was very concerned about water damage, then yea go with the pre-action system. Given the delay in the activation for the sprinklers, if and when they go off, they will do little to control/extinguish the fire, BUT perhaps they will prevent the spread of the fire and protect the building. Either way the contents of the shelves will have significant damage.

This may be a good time to ask the client how important are the records and can they be recreated with little or no $$ or loss of business. If the answer is NO, better have the client think again about this type of shelving system. Remember just because it is on site does not mean we can protect it.



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Fire Sprinklers Save Firefighters’ Lives Too!

My point about the pre-action system suggestion was that it does absolutely nothing to resolve the clearance issue. It would only result in a huge increase in the project price and cost the building owner time and money for the inspection and maintenance.

I know some people hate the question, but where are the possible igintion sources in the room.

Just taking a wild guess but the files are manual??? no electic motors???

Than about all that is left is lights and the smoker some one will bring up.

So the possibility of a fire starting in here???

Add more sprinkers????

You may be able to use an alternate extinguishing system, like FM200.

Don Phillips

Rather than speculating on a suggested fire protection design which may offer little or no solutions I suggest you read the attached paper and recognize that this problem does not present intuitive solutions:


I'll sit back and await the results of the suppression theory equations and fire tests that are performed. For now, this paper offers some relatively good interim measures.

Sorry

I neglected to attach the test report. Tom was again correct in that smoke detection is important for these installations. I would also consider fire-resistive separation of storage rooms from the remainder of the tenant spaces or occupancy.


I can see some real firefighter awareness issues that need to be communicated to responders - especially given the number of these systems installed in law offices, whom seem to always have the really nice offices on the top floors of high rise buildings.

Thank you very much for the info stookey. I didn't get all the way through the test report but the general report and determinations was very interesting. I don't want no part of them

Cidona

This a unique case where fire detection in combination with fire-resistive construction will work well. In a sprinklered building this storage configuration requires a high degree of respect.

I understand from the FPE supervising the tests that the test results will be reflected in NFPA 13. This is a problem because this style of storage needs NFPA 72 compliant detection.

Based on my discussions with the supervising FPE the problem needs more tests but it offers enough for lower-level archieve fire risks.

Stookey

Thanks for posting the links to the information, very interesting reading. This is yet another case where we think just put a sprinkler in place and everything will be OK. After all it works so well so many times before, why not here? Just think this all got started with the old 18" rule and how to make it fit. So perhaps in a few years we will have an answer, and a code section to reference for this hazard. But just think of all of these storage units that will be sold between now and then. I wonder if the manufactures are aware of the test results and the fire protection problem they are creating by installing the product??

Smoke detection, and a rated fire enclosure seem the way to go. Smoke is an easy fix, BUT the rated fire enclosure will be the challenge on retrofit applications. Yea I know you can not ask for this after the fact, put I sure can!

I believe CDA asked the question where is the source of the fire? Some of the larger units have electric motors to move the units. Also you can not forget our friendly arsonist. I recall a large record storage fire in NJ in the 1990's where an arsonist got to two 100K sq. ft. record storage warehouses to damage records.

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Fire Sprinklers Save Firefighters’ Lives Too!