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

Free Signup

Our daily posts run during study season (June - October). Subscribe for posts on PE Problems and Daily Discussions, straight to your inbox, for free:

Standings

Complete Standings for the Weekly Exam Series:

Now Available:

2018 PE Prep Guide

Weekly Practice Exams

Filters

Archives

August 2018
July 2018
June 2018
May 2018
November 2017
October 2017
September 2017
August 2017
July 2017
June 2017
November 2016
October 2016
July 2016
June 2016
June 2015

Daily Discussions

Daily discussion questions are open-ended questions posed by members for the benefit of sharing expertise and learning from other perspectives. Join as a member here.

PE Problems

Visit July-October for daily Fire Protection PE Exam sample questions.

Solutions are posted the day after posting.

Comment with your solutions, questions or clarifications.

Please note that questions posted are unofficial and in accordance with NCEES rules are intended to be similar to actual exam questions, not actual exam questions themselves.

RSS Feed

Home - About - Blog - Contact - Exam Prep - Store

Copyright © 2018 MeyerFire, LLC
The views, opinions, and information found on this site represent solely the author shown and do not represent the opinions of any other party, nor does the presented material assume responsibility for its use. Fire protection and life safety systems constitute a critical component for public health and safety and you should consult with a licensed professional for proper design and code adherence. Some (not all) outbound links on this website, such as Amazon links, are affiliate-based where we receive a commission for orders placed elsewhere.