Discharge time of Cooling Water to Hydrocarbon Tanks

[miltiadis]

Hi, I would like to ask if anybody knows what is the minimum discharge time for cooling water to tanks containing Hydrocarbons according to NFPA (or any other code).Thanks in advance

 

[DavidCR]

I have not found a direct NFPA reference for this, a related point is in NFPA15(2003) considering fixed spray systems

7.4 Exposure Protection.
7.4.1* General.
7.4.1.1* A system for exposure protection shall operate as intended for the anticipated duration of the exposure fire.
A.7.4.1.1 In determining the duration of the exposing fire, consideration should be given to the properties and quantities of the exposing combustibles and the anticipated effect of available manual fire fighting. System operation for several hours may be required.

In specific applications (like deluge systems for tranformers) per NFPA15/850 1hr is indicated.

FM data sheet 0788 indicates 2 to 4 hrs. depending on the case, you can get if for free on FM Global.