Contest: Cigars ablaze!

[buzz]

Brothers and sisters! I got a letter from NCEES notifying me that I PASSED the Fire Protection Engineering exam that I took in October last year. I couldn't be happier and I would like to share my joy by sending some of my favorite sticks to whoever can solve this fire protection question. The person whose answer is the closest will win. In the event of a tie, the person who has the most interesting approach to solving the problem will win. This question is pretty close to one of the ones I had to solve on the test...

Rules:

1. You MUST show your work, but it doesn't have to make sense - be creative.
2. One guess per person.
3. Edited posts are disqualified.
4. No farks allowed, must have at least 50 posts.
5. Contest ends Sunday, January 17 at midnight

You are sound asleep in your bedroom when a crazy ex-girlfriend breaks into your house and finds your humidor. In a jealous rage she dumps all of the cigars from the humidor (a total of 150) in the middle of your living room. The crazy chick then pours some tequila on them, lights them on fire and jumps out the window. Luckily, you installed a fixed temperature heat detector in your living room due to your wife's concerns over the fireplace, which you converted from wood burning to gas last year.

• The average size of the cigars is 5x50 cause you really dig those Robustos.
• The Heat Release Rate of 1 cubic foot of tequila-soaked cigars can be assumed to be 250 BTU/s.
• The inside temperature is 75 degrees F because your wife is always cold.
• The detector alarm temperature is 135 degrees F.
• The ceiling height in the living room is 10 ft and the ceiling is flat.
• The heat detector is located on the living room ceiling, approximately 2 ft. from the centerline of the fire.
• The Response Time Index (RTI) of the heat detector is 100.
• The fire can be assumed to be Steady State.

How many seconds will it take for your heat detector to be set off, awakening you to the nightmare in your living room?

Hint: It will take less than 5 minutes (300 seconds).

Here are the guesses so far (will be updated):
mail man = 133
Eville = 32
slcraiders = 60
SirPuffsAlot = 8
badwhale = 299
cinda = 36
Irish79 = 73


Good luck!
-Buzz

[mail man]

I say I would be awake and put the fire out before the alarm even goes off, because, my wife would have heard and known that the ex was in the area (a disturbance in the force). The alram, would not of even had a chance to go off, and the kiddies would remain asleep.

But really though, CONGRATS on passing, you had better smoke one of those things before you send any out.
Keith

[ashauler]

Congratulations on passing the exam Buzz!!

I would never hear the alarm go off, as I would be chasing the crazy bitch down the street with a hammer. The only sound I would be listening for is sirens.

[Lopaka]

Congrats on passing the exam!

My alarm system aka DOG would have gone off before she got in the house. My dog has a very distinctive "WERE GOING TO WAR!!!!" bark that gets my adrenaline running. At this point I would be running through the house with fists pumping and body in the we are going to war mode ready to kill!!!

After seeing the ex heading to the humi...well lets say...

You wont be seeing her again.

"A friend will have a drink, a real friend will help you hid the body."

Lopaka

[ndv21]

Buzz,

I had to read that 3 times just to understand it! lol

Congrats on passing the exam! I will let the other mathletes handle this one. I will sit back and enjoy the show

[buzz]

Thanks guys, I am pretty dang excited that I passed that test - I'll be smoking a celebration cigar this weekend with my wife!

Keith, Jamie, and Lopaka - you guys all can't guess 0 seconds...

Nelson, no math-nerdness necessary, just throw some numbers around and see if you get lucky.
Example: # cigars / RTI * indoor temperature = 150 / 100 * 75 = 113 (this of course is not the correct answer)

We are talking about some high quality smokes here... Blunts AND Swishers!

-Buzz

[mail man]

Thanks guys, I am pretty dang excited that I passed that test - I'll be smoking a celebration cigar this weekend with my wife!

Keith, Jamie, and Lopaka - you guys all can't guess 0 seconds...

Nelson, no math-nerdness necessary, just throw some numbers around and see if you get lucky.
Example: # cigars / RTI * indoor temperature = 150 / 100 * 75 = 113 (this of course is not the correct answer)

We are talking about some high quality smokes here... Blunts AND Swishers!

-Buzz

Well...That is what had me confused, I was figuring the burn rate for some real cigars

Actually, I was trying to read this and figure out how to answer this and my eyes went cross, and I am sure I heard a blood vessel in my brain pop.

[mail man]

okay, I am just throwing stuff out there, so please, don't tell me how I did this wrong, it might make my head explode trying to comprehend the workings.

My answer is 133 seconds, and this is how I got to it;

btu/ #cigars * ceiling height + temp rise = 250 / 150 * 10 + 70 = 133

Keith

[ashauler]

snip....., and I am sure I heard a blood vessel in my brain pop.

And I bet the echo was a real bitch.















j/k couldn't resist

[Eville]

Congrats on passing your exam! If you had a lot of questions like the one you asked on the exam, I can see why you are so excited.

As for the problem, I worked it out and came up with 2 answers, neither of which are probably close. I worked it out one way and got 31.7 seconds, and another way I got 1.7 seconds. I am going to go with the first answer of 31.7 seconds.

[ndv21]

# cigars / RTI * indoor temperature = 150 / 100 * 75 = 113 (this of course is not the correct answer)

Then what the hell is that example good for!!!!


J/K lol

[buzz]

Then what the hell is that example good for!!!!

I think the red-faced double-bird smiley makes me laugh more than anything on this site...

-Buzz

[badwhale]

I think the red-faced double-bird smiley makes me laugh more than anything on this site...

-Buzz

I think that is Kevin's personal smiley

[slcraiders]

I am guessing it would take about double that amount of cigars to make up one cubic foot. so Approx 125 BTUs at a temp increase of 1 degree per second (another guess). So based on the detection temp and the current temp= 60 seconds?

Congrats on passing your test, btw.

[cigarsarge]

Just a wild guess...I think it would go immediately.

[dajones]

Fark? I guess that is a re-deployment of the old DOS attack lingo...

*sigh*

Yet another forum (I hang at BOTL and Puff) where I hafta establish some sorta bona fides before being allowed to play.

Good luck guys!

[bigwhiteash]

Fark? I guess that is a re-deployment of the old DOS attack lingo...

*sigh*

Yet another forum (I hang at BOTL and Puff) where I hafta establish some sorta bona fides before being allowed to play.

Good luck guys!

Don't like it?

The door is in the upper right corner.

[ashauler]

....snip
Yet another forum (I hang at BOTL and Puff) where I hafta establish some sorta bona fides before being allowed to play.

Good luck guys!

Yeah, this place is very different than those two, thank goodness.

[dajones]

• The average size of the cigars is 5x50 cause you really dig those Robustos.
• The Heat Release Rate of 1 cubic foot of tequila-soaked cigars can be assumed to be 250 BTU/s.
• The inside temperature is 75 degrees F because your wife is always cold.
• The detector alarm temperature is 135 degrees F.
• The ceiling height in the living room is 10 ft and the ceiling is flat.
• The heat detector is located on the living room ceiling, approximately 2 ft. from the centerline of the fire.
• The Response Time Index (RTI) of the heat detector is 100.
• The fire can be assumed to be Steady State.

Hmmm

okay, we need something like /ceiling jet lag time (assume 1.2) = .833

we need radial distance to detector (stated as 2 feet)

we need height of ceiling (10 feet)

and heat release rate (given = 250 btus)

raise radius to 11/6 = 2^11/6 = 3.56

Now calc release rate^1.3 times height^1/2

BUT: convert BTU to KW (what, like... BTU/minute equals 0.01757 kilowatt so 250*60/0.01757 =~ 854,000kw/min)
I'll prolly hafta get back to heat release conversions...

T=1/(jet lag) * 3.56/10^(0.5)*Heat Release^(.333) = ~3/(3.2*Heat Release)

I kin already see Imma WRONG cuz this is gonna make a rilly smaaaallll #....

Back ta the drawing board

[dajones]

Don't like it?

The door is in the upper right corner.

Well a big ole HOWDY to you too, pardner!