Understanding the basics of these fire protection devices and how to determine which types you need in your motorhome.
By Mac McCoy, RV Alliance America, C95
Most people know it’s wise to keep several fire extinguishers in an RV, car, boat, and house. However, going through the process of choosing which fire extinguisher is the best for each situation can be difficult. There are a variety of fire extinguishers on the market and a number of factors that affect each individual’s buying decision.
As I travel across the country training RVers to be fire-safe with my “Fire & Life Safety” seminar, there are a few questions I repeatedly hear:
- What do the numbers and letters on the fire extinguisher mean?
- Is my extinguisher safe to use around my children and animals?
- How much cleanup is required when the contents of my fire extinguisher are expelled?
- How much does a good fire extinguisher cost?
Knowing the answers to these questions will help you to determine which extinguisher is right for your needs.
What do the letters and numbers on the fire extinguisher mean?
Fire extinguishers may have one or more letters on the label “” A, B, C, D, or K “” and a number from 1 to 120. The letters A, B, C, D, and K represent the types of fire the device can extinguish.
- Class A fires involve common combustibles such as paper, fiberglass, wood, 12-volt wiring, and many other items commonly found in a home, RV, or boat.
- Class B fires involve flammable and combustible liquids and gases such as gasoline, diesel fuel, and propane.
- Class C fires involve energized 120-volt electrical equipment, including wiring, fuse boxes, circuit breakers, machinery, and appliances.
- Class D fires involve combustible metals such as magnesium, sodium, potassium, sodium-potassium, alloy uranium, and powdered aluminum.
- Class K fires involve restaurant grease.
If any of these symbols are missing on a portable fire extinguisher, the extinguisher has not been rated for that particular class of fire.
The numbers on the label represent the area the extinguisher will cover. Class A extinguishers are measured in cubic feet (1A equals 8 cubic feet). Class B extinguishers are measured in square feet (10B equals 10 square feet). There is no area measurement for Class C extinguishers.
Types of fire extinguishers
There are a variety of fire extinguishers on the market. Some are designed for personal use and some for professional use. Following is a list of the fire extinguishers available today.
ABC Dry Chemical: The material used in this type of extinguisher is monoammonium phosphate, a hazardous material that can be toxic. It has a very limited Class A fire-fighting ability. With this type, a very large ABC dry chemical extinguisher is required to handle a small Class A fire. Once the contents are expelled, the ABC dry chemical extinguisher is very expensive to clean up. The cost of this type of extinguisher is $10 to $150, depending on its size.
Purple K (PKP) BC Dry Chemical: The material used in this type of extinguisher is potassium bicarbonate “” also a hazardous material. The military and airports are the main users of the PKP type extinguisher. It is available on a limited basis and is expensive “” $20 to $50 each “” depending on size.
BC Dry Powder: This is the most common and least expensive extinguisher. It uses non-toxic sodium bicarbonate. In a non-motorized RV trailer, regardless of size or type of construction, only one 5BC extinguisher is required by the National Fire Protection Association. For a motorized type A, B, or C motorhome, no matter the size, a 10BC extinguisher is required.
This extinguisher is messy to clean up but is popular because of its low price. A BC Dry Powder extinguisher can be purchased for as low as $6. The price goes up to approximately $60 for a larger size. It’s important to note that the BC Dry Powder extinguisher is not designed to fight Class A fires that involve common RV components such as fiberglass, wood, and fabric.
Halon: No longer available to the general public, these extinguishers are very hazardous when used on a fire because of a chemical change that takes place during the heat phase of the fire. According to the material safety data sheets, halon changes to hydrogen fluoride, hydrogen chloride, and hydrogen sulfide. During the cool-down phase, it changes one more time into phosgene gas. Although halon was initially thought to absorb oxygen, it actually displaces oxygen in the area of the fire. Halon is clean and requires little cleanup; unfortunately, it’s highly toxic. It costs an average of $150 per pound.
Halatron: This extinguisher is a popular replacement for halon. It is environmentally friendly but still has some of the same hazards as halon during the heating and cooling process. Halatron is very expensive for the average RVer, boater, or homeowner. A 23-pound 1A 10BC extinguisher costs approximately $250, and a 2A 10BC costs approximately $350.
AB-type wetting agent from Cold Fire: The wetting agent is a chemical compound that when added to water materially reduces its surface tension. This increases its penetrating and spreading ability. Commonly used in the auto racing industry, it is non-corrosive, non-toxic, and biodegradable. This extinguisher system is ideal for RVs and boats and is available for purchase at many RV rallies and auto races.
The Cold Fire product has been on the market for more than a decade. The wetting agent from Cold Fire is used in preinstalled extinguishing systems for RV engine compartments and may be used as a replacement for halon systems in some boats. Very little cleanup is required once the wetting agent is released, and it costs from $6 to $450, depending on its size.
ABC New Designer Foam:
Available since 1999 and manufactured by Kidde, the material in this extinguisher is a non-toxic new generation of foam, popular because it is safe around children and animals. It is effective on both vertical and horizontal surfaces; is easy to use; and requires very little cleanup.
This extinguisher is ideal for RVs and, with the proper Coast Guard-approved bracket, can be used in some boats. ABC New Designer Foam is not available in all states, so check for it at RV rallies. It costs approximately $40.
ABCDK Allfire Designer Foam: Hawk International has offered this product since 1995. The material in this extinguisher is non-toxic, non-corrosive, biodegradable, and friendly to children and animals. It is easy to use, even for someone who has limited use of his or her hands. It cleans up with little effort; has the ability to hold vertically; and flows easily into areas most extinguishers cannot reach.
The ABCDK Allfire Designer Foam extinguisher has the ability to cool even the hottest materials. Its biggest value is the ability to emulsify hydrocarbons, such as gasoline, motor oil, and diesel fuel, so they cannot reignite. This extinguisher is ideal for all applications. Small, handheld units cost $20; larger refillable bottles cost $120; and 5-gallon or 55-gallon bulk containers are available for $20 per gallon.
Aqueous Film-Forming Foam (AFFF): The fire service and military have used this type of foam for more than 40 years. It is slightly toxic and corrosive and has not been readily available to the public. There has been little or no education on this type of extinguisher for use in the RV or boat industry.
The AFFF cools fuel and smothers a fire by forming a foam blanket. Firefighters must be careful not to disturb this blanket, because vapors can reignite. This type of foam does not cling very well to a vertical surface. When AFFF is used, the foam requires cleanup and then the surface it covers requires cleanup as well. AFFF is sold only in 5-gallon to 55-gallon drums. It costs approximately $30 a gallon.
Who’s looking out for you?
An association called the National Fire Protection Association (NFPA) acts as an advocate for public fire safety. Among other things, the NFPA makes recommendations for the type, size, and location of fire extinguishers for businesses and industry.
Fire departments and fire extinguisher companies that refill and service extinguishers are the watchdogs that ensure the NFPA’s standards are met. Thanks to their standards, fire extinguishers can be found in public buildings and are required in RVs, boats, RV parks, and service stations.
Although the NFPA standards are for the most part positive, the standards require the use of certain older-style extinguishers such as the dry powder and dry chemical extinguishers. If you have ever used a dry powder or dry chemical fire extinguisher, you’ll remember the mess it created. Moreover, it may not have put out the fire or kept it out. Some of the so-called clean agent halon and CO2 extinguishers will lose some of their effectiveness on a windy day and in confined spaces, such as an RV or boat. They also can be heavy and expensive.
What’s best for your situation?
The NFPA regulates fire extinguisher use in business and industry, but, unfortunately, there is no national association that promotes fire extinguisher safety and maintenance to the public. Due to this lack of information, the public is rarely informed when a new fire extinguisher is released onto the market, including some impressive advancements in extinguisher technology that have been introduced during the last 10 years.
As a former firefighter and full-time RVer myself, I’ve done extensive research on the products that best meet the unique demands of a fire occurring in the confined space of an RV. Without reservation, my recommendation is one of the designer foam extinguishers. As mentioned above, they come in ABC New Designer Foam and ABCDK Allfire Designer Foam.
Checking your fire extinguishers
Once you’ve determined that you have the right type of extinguishers, the next priority is to keep them properly maintained by checking them periodically. Check the fire extinguisher gauge to determine whether there is pressure in the extinguisher. If the gauge indicates empty or needs charging, replace or recharge the extinguisher immediately. To test non-gauged extinguishers, push the plunger indicator (usually green or black) down. If it does not come back up, the extinguisher has no pressure to expel its contents. If you need help testing your fire extinguishers, check with your local fire department.
Do not pull the pin and expel the contents to test your powder extinguisher. If you use a portion of the powder extinguisher, have it refilled or replaced immediately. When you have a fire extinguisher refilled, ask to shoot off the charge first (most refill stations have a special place where this can be done safely). This lets you see how far it shoots and how long a charge lasts.
It is also extremely important for RVers to become well-versed in fire and life safety. Your life and the lives of your loved ones may depend on it.
Mac McCoy is a 33-year fire-fighting veteran who has worked as a paramedic, deputy sheriff, and, most recently, the Fire Service Training Coordinator for the state of Oregon. He has a bachelor’s degree in fire science and a master’s degree in fire administration. He has taught fire safety to thousands of civilians and firefighters across the United States and abroad.
For more RV fire and life safety information, visit www.firesafety.rvaa.com or attend one of the “RV Fire & Life Safety” seminars presented by Mac McCoy at FMCA international conventions and many area rallies. This seminar is cosponsored by FMCA and RV Alliance America and includes classroom time as well as an opportunity to fight a fire with various types of fire extinguishers.