PE Problem #9

6/13/2018

Inergen (IG-541) is being used for protection of several rooms which contain highly valuable historic documents. If the fire type is considered Class A and the design concentration of Inergen is provided, determine the clean agent-air mixture density.
a. 1.15 kg/cu. m
b. 1.25 kg/cu. m
c. 1.28 kg/cu. m
d. 1.44 kg/cu. m

Solution | Posted 06/14/18

10 Comments

FPE

6/13/2018 06:52:42 am

c. 1.28 kg/cu. m (SFPE 5th ed, Page 1526, Clean agent - air mixture density formula)

Rob

6/13/2018 09:43:14 am

c 1.27866

EdwH

6/13/2018 11:40:18 am

SFPE 5th
Table 44.17 IG-541 34.2 %
pg 1526 mixture density (kg/cu m) = 1.28 for Vd = 1.43

Ans == c.

David

6/13/2018 12:18:20 pm

1.28 kg/cu m

6/13/2018 02:18:26 pm

Orihara

6/13/2018 11:39:46 pm

Does the equation exist in SFPE 5th?

Orihara

6/13/2018 11:40:28 pm

I meant SFPE 4th.

jakes

6/14/2018 09:14:16 am

I don't have the 5th ed so I also use the 4th ed. Would really find it useful if reference was given to the 4th ed as well.

DIAA

6/15/2018 04:46:57 pm

D) 1.44 as per table A.5.4.2.2(b) class A min concentration for IG 541 is 34.2 then go to table A. 5.5.2 (f) at temp 21 with formula S=0.65799+0.00239 * 21.= 0.708 m3/kg which leads to denisty of 1.44 m3/kg

DIAA

6/15/2018 04:56:21 pm

I was not correct as I didnot proceed to extract the denisty of Mix with air it should be

1.44 kg/m3 x ( 34.2/100) + 1.202 kg/m3 x (100-34.2)/100= 1.28 kg/m3

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