Sprinklers for storage building

[garfio]

I am trying to do a preliminary sizing of a sprinkler system and need some assistance to clarify what seems to me unclear in NFPA standards.

The area to sprinkler is a non-combustible storage building for bulk (loose) storage of wood pellets. The pile will be higher than 12 ft. The area is about 30,000 sq.ft. Product from the pile will be loaded to trucks with front-loaders.

NFPA's Fire Protection Handbook categorizes storage as bulk storage, solid piling, palletized storage and rack storage (Don't know if these categories are also defined in a standard). Bulk storage consists of piles of loose, free-flowing materials, while solid piling consists of cartons, boxes, bales, bags, etc in direct contact with each other. My application is clearly "bulk storage" and not "solid piling" or "rack".

However, under "Storage" NFPA 13 has requirements for palletized, solid piled, bin box and shelf storage only (besides special storage, tires, etc.). There is no mention to bulk storage.

So:

- Where are the requirements for bulk storage?
- Should this lack of information for bulk storage is saying that there is no need for sprinklers if storing in bulk?
- Should I design the sprinklers using the general requirements (chapter 11) or using the
requirements for storage (Chapter 14)?

Just in case somebody asks why to use sprinklers, this is based on IBC/IFC 2006 requirement for storage in areas larger than 12,000 sq.ft. In that same building/fire code there is also a requirement for sprinklers for high-piled storage (> 12 ft).

I will appreciate any comment or suggestion on how to solve this problem.

 

[stookeyfpe]

I answered this question last week:

http://www.eng-tips.com/viewthread.cfm?qid=249952&page=1

Is the question "What is the fire behavior of a big pile of wood pellets inside of a building versus the fire behavior of palletized bags or palletized bags on racks of wood pellets?"

If it is, you should first review the chapters on fire growth and behavior in the NFPA Fire Protection Handbook.

 

[garfio]

Thanks stookeyfpe but what I wanted to know is the approach that NFPA 13 has for loose bulk storage of a combustible commodity inside a building. I don't see that there is a specific reference to this kind of storage in NFPA 13, and as this standard is generally enforced by the AHJ, I would like to know what would their demand be.

I understand that a comparison between my case and others where the product is palletized or on racks, will provide a better understanding of the situation, but that would only be a personal opinion if not backed up by the standard.

Do you find that loose bulk storage is covered by NFPA 13? Where?

 

[KDLLC]

You'll find sprinkler protection criteria for idle pallets in NFPA 13 section 12.12 'Protection of Idle Pallets' (20007 version). If you have the handbook (Auto Sprinkler Systems Handbook, not the Fire Protection Handbook), the commentary decribes the serious fire challange that idle pallets can be. That section gives several protection options for storage heights greater than 12' - all of which will require large pipe & a darn good water supply.

Ed K

 

[LCREP]

I believe bulk pile storage is out of the scope of NFPA 13. Take a look at the FM Data Sheets, they are free here

http://www.fmglobal.com/FMGlobalRegistration/default.aspx?action=new.

They have sprinkler requirements for the storage of wood chips, Data Sheet 8-27.

These types of fires are hard to control because of the deep seated fires that occur. You have to get in an tear the pipe apart. The sprinkler proteciton listed above would protect the building structure, maybe.

If you read NFPA 13, the definitions for Extra Hazard Group 1 and or 2 , you could pick the density from here if you really want to use a NFPA document.





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Fire Sprinklers Save Firefighters’ Lives Too!

 

[garfio]

Thanks you all for the input.

KDLLC: My commodity is wood "pellets" that is, compressed wood 1/4" diameter x 1" long. I think you understood them as pallets. Stacked pallets leave more empty space for air to flow, and probably the fire will progress rapidly. As LCREP mentioned, bulk pellets have a different kind of problem.

 

[KDLLC]

Yes, my mistake. Pallets and pellets are two completely different animals. Sometimes the eyes see what is familiar instead of what is real.

Ed K