TB 145 - Combustible Metals Flashcards
What application when utilized on combustible metal products has the potential for explosive results?
Water
Most combustible metal fires produce extreme temperatures ranging from what degrees?
5000 to 9000 degrees
Temperatures at 5000 to 9000 degrees are high enough to separate water into what elements?
Hydrogen and oxygen
Fire involving combustible metals are designated as what class fire?
Class D
What is a factor in determining ease of ignition, rate of burn, temperature generated, and the explosive potential of combustible metals?
Surface area
Which poses a greater hazard and when exposed to fire conditions can result in explosion, small or large metal pieces?
Small
What 2 types of metals can combustible metals be divided into?
Alkali metals
Alkali earth metals (transitional, other metals)
Which type of metal is water reactive under no fire conditions and should be placarded with the “W” under the NFPA 704 system?
Alkali metals
Alkali metals are highly reactive and are usually stored immersed in what?
Mineral or kerosene (paraffin) oil
Which type of metal when burning can become extremely dangerous when in contact with water?
Alkali earth metals
Full compliance of all businesses who are found utilizing combustible metals will require and NFPA 704 placard with a “W” by when?
January 2011
Placard shall be indicated by an “M” in the 4th space if the quantities or form
Meet LAFD criteria for placarding in excess of 500 pounds of combustible metals or that process or store how many pounds or less of combustible metals in dusts, chips, powders, turnings or ribbons?
500 pounds
For the NFPA 704 placard, if multiple hazards exist, how many symbols are limited to the placard and how are they positioned on the placard?
No more than 2, most severe stacked on top with lesser stacked in bottom
Unusual fire or smoke, “white hot” flames, presence of flowing or molten metal and white colored smoke indicate what kind of burning material?
Combustible metals
Members working within how many feet of a burning metal product are considered to be working in an IDLH?
30 feet
Extinguishment of combustible metal fires is accomplished through what affect of the burning material?
Smothering
Utilizing water, foam, purple “K” or dry chem extinguishers can disrupt the process and actually make the fire what?
Worse
Which is the only approved product provided by the LAFD to extinguish combustible metal fires?
“MET-L-X”
How many pounds of MET-L-X does supply and maintenance have?
500 pounds
According to the manufacturer, how thick of a layer of MET-L-X is required to effectively smother a fire?
1”
How many pounds of MET-L-X is required for every one square foot of fire?
10 pounds
What is MET-L-X made out of?
Salt base with an added polymer for sealing
The entire stock of MET-L-X maintained a supply and maintenance would only extinguish how many square feet of a fire?
50 square feet
Purple “K” is appropriate for what class fire only?
A, B, and C
What type of power extinguisher combustible metal fires?
Dry
If a small amount of product the size of what may be separated from exposures by a fully encapsulated firefighter through use of shovel or similar tool?
Size of a waste basket
It may be appropriate to attempt to extinguish the product using what if found on site?
Dry sand
Firefighting operations will be primarily defensive, however firefighters moving what away from exposures may be possible?
Dumpster with wheels or 55-gallon drums
Metal fires will burn quickly and begin to develop an oxide crust that will limit open burning material, the crust should not be distributed until the point of extinguishment which can take up to or longer than how many hours?
24 hours
