As disastrous as it can be, an RV fire doesn't have to happen if you plan ahead. But if a fire begins in a motorhome, it won't take much time until the RV is totally consumed in flames, unless you take some precautions.

Your typical motorhome is constructed from highly flammable materials. Add in the fact that your motorhome carries propane plus either gasoline or diesel fuel, throw in a maze of electrical systems and wiring and then bounce it down the road until something fails, and you quickly realize that there is a fair amount of potential for a fire to start.

Most RV fires begin in one of two areas: Typical RV refrigerators utilize evaporative cooling, which utilize a propane burner or electric element to provide that heat. If the propane burner on the back of the refrigerator overheats it can easily start a fire.

On a rear-engine diesel pusher there is also the potential for an engine bay fire. Diesel engines are turbocharged and the turbocharger gets very hot during operation, especially when climbing grades. If a hydraulic line or fuel line were to leak, it can easily spray fuel over the engine compartment. Once ignited by the hot turbocharger, it can quickly get out of control.

RVs are equipped with a fire extinguisher, per NFPA code. However, these only meet the minimum requirements set by law. It has no bearing on its ability to adequately extinguish a fire in your RV. It's generally undersized and not up to the task.

There are many classes of fires, and not all extinguishers are rated for every classification. Before we can understand the various types of fire extinguishers, we first need to understand fire itself. To do this we'll take a look at the fire triangle, which is used to help illustrate the basic elements present in a fire.

A fire is actually a rapid chemical reaction. In order to begin, or sustain, that reaction, you need to have three key elements present: fuel, oxygen, and heat. If you remove any one of these elements, fire cannot be sustained. In order to extinguish a fire, you must be able to eliminate at least one of these elements.

Fuel, Oxygen, and Heat
In an RV there's an overabundance of fuel. RVs are made with a large amount of wood and composite materials and use extensive amounts of glues and insulating foams. In addition, there's plenty of wiring, which has burnable insulation, as well as propane and gasoline or diesel fuel present. The interior furniture, bedding, drapery, carpeting, all combine to assist a fire and let it spread rapidly. You need oxygen to have fire too. It's everpresent in and around the RV.

Then these combustible materials only need to be raised to their combustible temperature and ignition will occur. An electrical short creates intense heat in the wire. Generally this wiring is run through or around highly combustible materials, such as wood paneling, carpeting, etc. A hot wire can easily cause any one of these fuels to ignite.

Class-A Fire
Class-A fires are created from solid combustible fuels (other than metals). Examples of this are wood, paper, cloth, and plastics. Class-A fires leave ash, so think of the word "ash" to help remember what an "A" fire is.

To extinguish a Class-A fire, you can either separate it from its oxygen or cool it down below its flash point. This is the easiest fire to put out, and plain water works. Ideally you'd add an element to the water (soap works) to break the surface tension and separate the fuel from its oxygen, allowing the water to further cool down the fuel.