Storage of Group A plastic

[SprinklerDesigner2]

I am 99% sure I already know the answer but I got to ask anyway.

Currently we are operating under NFPA #13 2002 edition but word is we will move to 2010 in January. I know I could use the 2010 now but we can drop back to 2002 if we can make this work.

Storage of fabrics are primarily exposed polypropylene and take up about 30% of the storage space. Total building size is 37.500 sq. ft.. While the photo shows storage higher than 5'-0" I have been told storage height will be limited to 5'-0". We know how this works but I know the customer and from past experience when they say they will keep storage below 5' they will enforce it.

Existing system was design to a .30 over 2,000 but when I conducted the flow test on the property I got 65 static, 27 residual @ 769 gpm.

I can get a .20 over 1,500 with 250 hose but that 500 gpm hose stream requirement kills me.

From 2002 Table 12.1.10.1.1 Discharge Criteria for Miscellaneous Storage and Commodity Classes I through IV Storage 12 ft (3.7 m) or Less in Height under Miscellaneous Group A Plastic Storage Curve 3 (.20/1.500) is fine but 500 gpm hose is required. It's obvious the 500 gpm hose requirement is killing me.

Did I read this right, is the 500 gpm hose requirement required or is there some way around it by arranging the storage?

 

[LCREP]

Take a look at NFPA 13 in the commodity Annex A, see below. I would call it a class IV commodity based on NFPA. If the product is NOT on racks and not higher then 10' high all you need is .20/1500 and 250gpm for hose as per Table 12.1.10.1.1 Discharge Criteria for Miscellaneous Storage.

Cloth
Cartoned and not cartoned
- Natural fiber, viscose Class III
- Syntheticd Class IV

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[SprinklerDesigner2]

To call it a Class IV would be music to my ears but I think it is a Group A plastic.

It is something we have all seen... it's the plastic matting you see placed atop freshly seeded highway berms holding dirt in place giving grass seed time to sprout.

 

[LCREP]

U are correct now that you provided more details. BUT if you look at the 2010 ED of 13 Table 13.2.1 Discharge Criteria for Miscellaneous Storage 12 ft (3.7 m) or Less in Height, see below, you should be OK.

Grp A Plastic

Exposed, Unexpanded and expanded, Palletized, height ≤5, OH2, hose 250

You should be good as per the section below from NFPA 13, 2010

15.2.1 For the storage of Group A plastics stored 5 ft (1.5 m)
or less in height, the sprinkler design criteria for miscellaneous
storage specified in Chapter 13 shall be used. The protection
criteria in Chapter 13 shall be acceptable for storage of
Group A plastic commodities up to and including 5 ft (1.5 m)
in height. (See Table 13.2.1 for specific GroupAplastic storage height
protection criteria.)


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Fire Sprinklers Save Firefighters’ Lives Too!

 

[Sdpaddler50]

I think you have a high fuel load for an OH2 (.2/1500) density, especially if you have a wood roof. A 3 9 1 18 gives the definition of misc storage, and I am not sure you can apply this, based on what you have provided. I have worked with carpet storage warehouses in the past, and i have found these carpet backings (if that is what they are) tend to grow in size over the years - ie, pile size limitations to meet the misc storage definition may be difficult to adhere to. It's a tough one to protect without reinforcing or in-racks.

 

[SprinklerDesigner2]

LCREP,

The difference between Table 12.1.10.1.1 2002 Edition and Table 13.2.1 is surprising to me.

For Group A plastic < 5' 500 gpm hose is clearly called for in 2002 while Table 13.2.1 calls for 250 gpm hose is called for in 2010.

Sdpaddler50,

Metal building having bent metal purlins and metal roof deck.

 

[LCREP]

Glad I can help. I do not have the 2007 ED of 13 on this lap top, I will check tomorrow and let you know if it changed in 2007 or 2010.

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[MGXFP]

I would check the specs on that geogrid (plastic matting) and see what it is made of. NFPA 13 lists specific types of Group A,B,C plastics (or at least the 2010 edition does).

 

[SprinklerDesigner2]

Newton,

I checked with the chemical engineer for the company and he told me it was polypropylene so it is a Group A.

 

[MGXFP]

You even said it was polypropylene in your first post! Go me for reading comprehension!