NFPA-13 Chapter 17 section 17.3.1.5

[Livlevu]

Dear All,
I would like to undrstand : For cartoned storage of Gr.A plastocs, I can choose figure 17.3.1.7 with discharge density of 0.3 GPM (when storage above top level is up to 5 ft) ?
For the same figure - is the damnad for discharge density of cieling sprinklers of 0.45 GPM is general to the figure or only in case of exposed plastic ?
Thanks !
Livlevu

 

[stookeyfpe]

I'm not sure which edition of NFPA 13 being used in your example. I am using the 2013 edition. Your question appears to be asking about the ceiling sprinkler demand for the protection of cartoned Group A plastics using control mode density area (CMDA) sprinklers. Using the 2013 edition I believe you're asking about Table 17.3.1.3.

This table prescribes the ceiling sprinkler density for the top level of storage above the highest level of in-rack sprinklers. When the highest pallet load in the rack is located above the highest row of in-rack sprinklers, this table is employed to determine the ceiling discharge density. If the top pallet load height is 5 feet, a density of 0.30 GPM/Sq.Ft. is required. If its > 5 but no greater than 10 feet, the density is increased to 0.45 GPM/Sq.Ft. In both designs a 2,000 Sq. Ft. design area is used.

 

[Livlevu]

Dear Sir,
I'm using 2016 edition.
Is the dammnad for discharge density of cieling sprinklers of 0.45 GPM is general to the figure or only in case of exposed plastic?
Livnat

 

[stookeyfpe]

The specified ceiling sprinkler density is only for the specific commodity and storage condition. It is not a once size fits all value. You need to review the section in its entirety when you are developing fire sprinkler designs for this high hazard commodity. Good luck.