The fire extinguisher must be UL listed or equivalent and fully
charged. The minimum for all vehicles is a UL Type 1-A:5-B:C. The
extinguisher need not be permanently mounted, but must be clearly
visible and readily available.
Now I know this sounds complicated but it is really quite simple.
The following chart will help you in remembering what Classes A, B
and C are all about:
Fire extinguishers with a Class A
rating are effective against fires involving paper, wood,
textiles and plastics. The primary chemical used to fight these
fires is monoammonium phosphate, because of its ability to smother
fires in these types of materials.
Fire extinguishers with a Class B rating are effective
against flammable liquid fires. These can be fires where cooking
liquids, oil, gasoline, kerosene, or paint have become ignited. Two
commonly used chemicals are effective in fighting these types of
fires. Monoammonium phosphate effectively smothers the fire, while
sodium bicarbonate induces a chemical reaction which extinguishes
Fire extinguishers with a Class C rating are suitable for
fires in "live" electrical equipment. Both monoammonium phosphate
and sodium bicarbonate are commonly used to fight this type of fire
because of their non-conductive properties. Class C fires are only
for active or live electrical circuits. If the power is shut off and
the fire remains active the "Class" would revert to the type of
material burning (Class A or B).
When you see a numeric beside the A or B it is showing you the
average square footage the extinguisher would be effective against.
Example 5 — B: flammable liquid fire no greater than 5 square feet
Remember when you were young and your mom put baking soda in the
refrigerator? She put it there to reduce odors and for a while it
would work. After a period of time you had to stir it up, as it
would settle into a seemingly solid lump and no longer work. Your
dry chemical fire extinguisher is the same way. Over time they will
settle and potentially not work when you need them the most! How do
we solve this problem? Easy, shake them up every now and then. You
will feel the solid in the bottom break up and become loose again.
Easy to do but very important for your fire extinguisher to be ready
when you really need it.
The A:B:C fire extinguishers can be found at all the major retailers
for home repair and improvements. Remember; 1-A:5-B:C is the
minimum. I have 1-A:10B:C in my home and shop as they seem to be
more readily available. Total cost for this larger size is in the
$20 range and the size is very close to that of a roll of paper