FM Data Sheet 8-9 - Storage Height for Exposed, Expanded Plastic

[Haldorson]

I have a nasty situation that involves an existing warehouse that has Group A exposed, expanded plastic. The owner would rather shut down the operation than install in-rack sprinklers.

What I'm trying to do is determine whether there is a maximum storage height permitted given the existing ceiling sprinkler system.

Existing ceiling sprinkler system:
-ESFR pendents, 17 K, 100 sq.ft. spacing, designed to protect Class IV commodities to 25' in height at 35 psi per sprinkler.

NFPA 13 does not cover Group A exposed, expanded plastics. Therefore I have turned to FM Datasheet 8-9.

It appears to me the datasheet provides no relief at all for having lower storage heights. It appears to me that if you have a ceiling of 30' and are storing the commodity to 1', 5', 14', or 25' the requirements are equal. Is this true?

I would like to be able to provide some option for the owner, even if it means 5' solid-piles or 8' of open rack storage.

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[LCREP]

See below for a document from NFPA Research Foundation

Link

They plan to start full scale testing I think this fall. But they plan on testing in-rack sprinklers and horizontal barriers.

I think a ceiling only system is not going to work with exposed expanded plastics, too fast moving fire.

Is the entire warehouse exposed expanded?

The owner may get his wish.....

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[Haldorson]

Not the entire warehouse. A single row of racks along one wall and solid-pile storage covering about 1000 sq.ft.

 

[stookeyfpe]

The client is screwed by ESFR panacea. Group A exposed, expanded plastics are outside the scope of their listing if these are Tyco sprinklers. For Group A exposed and expanded plastics, only the ESFR K=14 sprinkler is listed for expanded and exposed plastics. Any other ESFR K factor sprinklers aren’t listed for this commodity. Your client either pays for fire tests or you can switch to Tyco EC-25 and redesign the system for this sprinkler. ESFR does not = total fire protection.

One other option is to apply Figure 2303.7.4 from the 2009 IFC. Unfortunately for your client, I don’t think that one single row rack of plastic gives you an exception. You have a commodity load that either needs to be separated by an 1-hour fire barrier or you need to upgrade the automatic sprinkler system. The selected sprinklers were never designed for an expanded, exposed Group A plastic.

 

[LCREP]

Older versions of FM 8-9 had in-rack protection with ceiling area density design for expanded. Take out the ceiling ESFR protection, replace with an ceiling area density design, install a draft curtain between the ESFR and the new ceiling system AND instal a ton of in-rack sprinklers. Take the floor storage and put it on the racks. That is your only hope.

The other option is to store it off site at another location such as a public warehouse and go with just in time delivery. Keep it stored to 5' with the limitation on the number of pallets for "Mixed Commodities" in NFPA 13, 10 pallet loads in a 40K warehouse.

Who picked up on the expanded plastics in the warehouse?? Who ever did good find!! A fire in this area can take the entire building down.

Good luck delivery the news the owner does not want to hear. Been in your shoes many times. Make sure you put it in writing to protect your butt!

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[LCREP]

From FM 8-9 2005

Table 2.3.7.3(g) Control Mode Density Area Sprinklers, Single-Row Racks Without Solid Shelves, Storage Higher Than 25 ft (7.5 m)

Plastics:
Cartoned Unexpanded,
Uncartoned Unexpanded,
Cartoned Expanded,
Uncartoned Expanded

Storage Height Above Top IRAS Level, ft (m)

Up to 5 (1.5) 0.30/2000
Over 5 (1.5) up to 10 (3.0) 0.45/2000

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[Sdpaddler50]

Been there many times also. Uncartoned, Expanded plastic is a tough one if he won't go for In-racks. I know this is not a very good solution, but I have had clients store this outside the bldg., in truck trailers. Can be feasible if the amount is not too high. Then bring in limited amounts as needed, and store on the ground to max 5 ft high. This stuff does have the capability to burn a bldg down if not properly protected, especially if you have a wood roof.

 

[stookeyfpe]

Until about an hour after you left the building. I've seen building owners move high challenge commodities out of the building just long enough for the inspector to leave. Sometimes owners are driven to destroy their buildings because of their understanding of how he/she thinks the sprinkler system will perform.

 

[Sdpaddler50]

Stookeyfpe, yes, that is always a possibility, and it has defintely happened to me. But, people also forget to renew their quarterly testing contract, or shut a fire valve, and dont open it, or take their flammable liquids out of the rated room, and leave them in the middle of the plant floor...Just giving him some options that i said up front were not very good, but something to think about.

 

[Haldorson]

I appreciate all the feedback. Fortunately the owner has gone silent after I prepared a short summary of his options. Some jobs are best left on the vine.