School of the Boat 7Oct2008 - Some basics before we start

[JTheotonio]

I'm just trying to figure out a good start to Damage Control (DC).  So something pops into my head that maybe we need to cover some simple (very basic) topics.  Remember jargon should be in WWII, or as close as you can get. Here is a simple question.

Name the four "Classifications" of fires. Include the name, what fuel is being burned in each classification, and the type of extinguisher that is normally associated with putting out each classification of fire. No points for including Pink Lady or Hairy's secrete bottle of Capitan Morgan's Dark Rum.

One more fire related question:

Carbon dioxide (CO2) is a colorless and odorless gas that is produced by a fire when there is complete combustion of all of the carbon in the burning material.  The danger of asphyxiation from CO2 should not be taken lightly.

At what percent is CO2 dangerous to personnel in a confined space?

[Darrin]

That to me JT is the best place to start and I will keep from answering these questions unless folks are completely stumped   Let me know when or if I get to answer oh wise one

[JTheotonio]

Sorry Darrin I added an extra question to my first post. But nothing you should not know.

[Mark Sarsfield]

From what I remember from our fire safety training, the four classifications of fires are:
1) Wood, paper, and other combustible solids (other than metal) - Class A extinguisher
2) Combustible liquid fires - Class B extinguisher
3) Electrical fires - Class C extinguisher
4) Metal fires (i.e. magnesium) - Class D extinguisher

As for CO2 exposure, both quantity and duration are important.  According to this website (http://www.ccohs.ca/oshanswers/chemicals/chem_profiles/carbon_dioxide/health_cd.html) under 2% of air concentration is fine. 3.3% to 5.4% over 15 minutes causes increased depth breathing.  At 7.5%, a feeling of an inability to breathe (dyspnea), increased pulse rate, headache, dizziness, sweating, restlessness, disorientation, and visual distortion developed. Twenty-minute exposures to 6.5 or 7.5% decreased mental performance. Irritability and discomfort were reported with exposure to 6.5% for approximately 70 minutes. Exposure to 6% for several minutes, or 30% for 20-30 seconds, has affected the heart, as evidenced by altered electrocardiograms.

Exposure to 10% for 1.5 minutes has caused eye flickering, excitation and increased muscle activity and twitching. Concentrations greater than 10% have caused difficulty in breathing, impaired hearing, nausea, vomiting, a strangling sensation, sweating, stupor within several minutes and loss of consciousness within 15 minutes. Exposure to 30% has quickly resulted in unconsciousness and convulsions. Several deaths have been attributed to exposure to concentrations greater than 20%. Effects of CO2 can become more pronounced upon physical exertion, such as heavy work.

[JTheotonio]

That one was quick - True WWI jargon would have called the classifications Alpha, Bravo, Charlie, and Delta - not much different than now (ABCD).

WWII Damage Control handbook says this:   Although CO2 is not poisonous, unconsciousness can result from prolonged exposure at 10 percent volume and higher. Above 11 percent volume, unconsciousness can occur in 1 minute or less.

We are talking very confined spaces is a submarine. 

How about 100% on this question for you.  Good job Mark!

[Mark Sarsfield]

Thanks, JT.  I forgot about the phonetic alphabet in the reply. 

In addition, it's important to remember to aim the extinguisher at the BASE of the fire.  Especially, if it starts to climb the wall.

Finally, never, ever let your reenacting officers eat at a place called the Badlands in Ft. Gibson, OK.  We forced the cook and a few other swabs to take cover when we laid down a blanket of gas.

[Darrin]

there is one exception to the don't point the extinguisher any place other then the base of the fire and that was is what and why?

[Darrin]

So who knows what a "screaming Alpaha" is

[Mark Sarsfield]

I think flammable liquids might be the right answer to the aiming at the base exception, but it's been over a month since I did my fire safety training.  The purpose, in my mind, would be to prevent from spreading the liquid even more.

[Darrin]

Very good about the flamable liquids, (fuel oil, lube oil) the best way to combat those is IF you can bounce the AFFF off of a bulkhead and let it come down off of that and across it to smother it.. Be FOREWARNED though with a fuel oil fire and you have used AFFF, it can and WILL reflash IF the foam is moved before it cools completely off. There is a video online of a fireman working an oil fire in Hawaii and he was walking through it to get back to a ladder when he slipped and the whole damned thing went back up.

Sorry about that JT, I couldn't help myself with that answer and the next question about how to put out a Class "D" fire

[Mark Sarsfield]

I'll give someone else a chance to answer the Class D question.

[Ctwilley]

Did the Navy use the current phonetic alphabet? I don't know much about the Naval alphabet but I know that the Army didn't switch to the current NATO alphabet until the 50's. It was Able, Baker, Charlie, Dog, etc.. 

[Ctwilley]

Class Dog or Delta is a metal fire and is exting. using a dry chemical powder. The most common dry chemical extinguishers use Sodium Chloride, graphite, and copper powder.

[JTheotonio]

We used the phonic alphabet - it was the sure way of being understood in some cases.

It's OK Darrin - that was a good question.  A galley grease fire was not a good place to go splashing water around - stuff spreads like no tomorrow.  Diesel and lube oil with high flash points need to be contained fast.

[Darrin]

While on Torsk for the work weekend a friend of mine mentioned that when the boats in WWII went out on patrol they maximized EVERY space that they could get to store fuel oil to incluede the bilges and when they would start to empty the tanks they would pump the bilges to the FO tanks and use that and then clean them back out.
JT, I am going to be posting 2 very specific questions about FIRE that I feel very strongly about and I have already brought them up but no one is taking on trying to answer them so I am having to post them on the school of the boat by themselves. I am not trying to step on your toes with either one because this is YOUR block of instruction and not mine... Both questions have ment something to me over the last 18 years of service and I would hate to see anyone learn from the mistakes of others the hard way.