two remote area in Tire storage?

[mzg123]

Hi,

appriciate if anyone can clarify the following for me:

nfpa 13-2007-table 18.4(a)require the following for a tire storage-open portable rack-12 to 20 ft piling height:

0.6 gpm/sqft for 5000 sqft AND
0.9 gpm/sqft for 3000 sqft

and water supply shall fulfill both requirements.

does this also apply to hydraulic calculation? two remote area of protection? How?

Thank you,

 

[stookeyfpe]

The initial design area is beginning the suppression process. The secondary design area serves as the control mode sprinklers.

Tires are one of the most challenging commodities one can encounter. You must add both hydraulic demands together. Given the hydraulic demand that tires generate, you need to closely consider all variables.

Tires are a very challenging fire protection design and you may want to consider the services of registered FPE in this case.

Welcome to the world of what I call "either or" fire protection engineering.

 

[LCREP]

Ouch 5700 gpm can you say BIG pump(s) and BIG tank?? 5700 gpm x 180 minutes??= 1,026,000 gallon tank!! NOT including hose streams of 750 gpm x 180 minutes = 135,000 gallons!!!

Look at table 13-2007-table 18.4 (d) does ESFR work? demands are much less.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!

 

[mzg123]

Thank you stookeyfpe,

I am not going to design the system though I have done some sprinkler design. one of our client is concidering to move from a warehouse which can pile up to 12ft to a new warehouse (18ft height) to be able to pile up to 15ft. new ware house is sprinklered and been designed to
0.66 gpm/3000 sqft. also Columns in new warehouse have to be protected (sprinkler at 15'level) just they want to know if they can relocate or not,

 

[mzg123]

Existing Sprinklers are not ESFR, they have k=16.8 and 68C rating.

 

[stookeyfpe]

I don't know enough about what is being stored and this forum cannot resolve your client's problem. I know of someone in Southern Califoria that you can pay to fly to your warehouse of question at her $150/hour billable rate to figure out your problem. I can't help you - you need visual inspections and a solid H2O analysis before I venture into your hazard.

You have an "either-or" fire protection engineering problem.

Happy new year,

StookeyFPE

 

[chicopee]

I am quiet sure that you are not using the correct NFPA, it should be either 231 or 231C for the commodity that you are listing--unless things have changed again since I last was involved with such things.

I no longer have my NFPA 231C on plastic and rubber storage, however, I think that the two densities that you are quoting are based on two different sprinkler head temperature ratings. You must get a current copy of the NFPA relating to your commodity because the graphs and values are different from NFPA 13.

The 0.6gpm/sq ft may be based on a 286 deg F and the .9gpm/sq.ft on a 165 deg F.

Depending on your selection of head, your hydraulic calculation for that sprinklered area should have a flow rate equal to or greater then the above water demands of either 3000 gpm (=.6x5000) or 2700 gpm(.9x3000) and don't forget these values may have to be adjusted by some factors relative to storage pile heights. Again I emphasize get a current copy of the NFPA.

Yes, those values are for hydraulically calculated sprinkler systems.

 

[LCREP]

chicopee

231 and 231C were combined into NFPA 13, the 1999 edition and do not apply to rubber tire storage. He did quote the correct table in NFPA 13, 2007 edition for rubber tire storage.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!

 

[fireprotect]

first of all Happy New Year,

Thank you

yes the code that I have used is current and NFPA 231 was combined into the new NFPA 13 as LCREP mentioned.

0.6 & 0.9 gpm/sq.ft are both used for high temperature applications. and clearly is mentioned " 0.6 AND 0.9" and references to the note under the table 18.4(a) :" water supply shall fulfill both requirements"

my other question is that why this densities are not allowed for ordinary temperatire applications as per this table?

Thank you,

 

[chicopee]

Thanks for the update LCREP.

Fireprotect, do you know the sprinkler head temperature ratings at the stated densities.

Also, I believe that the reason for high temperature heads is that you'll get more concentrated water where the fire is originating. Too many heads would go off at lower temperature ratings.

 

[fireprotect]

high temperature sprinkler rating is 286 F ( 250 TO 300 F) according to TABLE 6.2.5.1 NFPA 2002

 

[mzg123]

Basically our client wants to move to new warehouse without any changes which impossible, the least that shall be done is to protect all columns or instead changing all sprinkler heads to ESFR and installing in rack sprinklers. still need more assesment of water supply. I don't think they move!

Stookeyfpe'
just for my interest about your answer to my question on two density requirements:
you mean the initial design area is beginning the suppression process and the secondary design area serves as the control mode sprinklers. then hydraulic calc should be done twice for both cases (once for 0.6@5000= 3000 gpm and once for 0.9@3000=2700 gpm)and compare pipe sizes and change them if necessary.
Am I right or am I missing something?

Thank you,

 

[stookeyfpe]

You need to calculate a concurrent demand. Go to YouTube, type in "tire fire" and you'll see why I am nervous about any high piled storage involving tires.

This is an internet forum, not the lunch box safety forum on the bed of my pickup truck. None of us are your fire protection engineer. If you are designing a sprinkler system for tire storage, you need to prepare two sets of calculations and make sure you can satisfy the two demands simultaneously operating. You have very large hydraulic demands that must be satisfied (i.e., big fire = big water).

This demand and commodity is why LCREP said "ouch." If you are nervous and you need design assistance, your client needs to open his/her checkbook and pay for professional engineering services. Frankly, I've told you enough to get you in trouble. Respect the opinions that have been presented in this arena and seek engineering guidance. This is not a NICET III job. The engineer of record most likely is pushing this design turd onto your plate.