There are three things you need to watch out for that can lead to a fire, often called the "fire triangle." What are they?
If you don't have oxygen, a fuel source and some kind of heat then you aren't going to have much of a fire. If all of these parts of the triangle are present, then a fire is not only possible but likely.
As a firefighter, what should you do with evidence at the scene of a fire if no investigator is present?
If the investigator has yet to arrive and you see evidence of what started the fire, you can do your best to salvage it from the burn as well as tag what you've seen and photograph it so the investigator can refer to it later.
Different fires can be started and behave in different ways based on the fuel source. How many classes of fires are there?
There are 5 classes of fires, and it's helpful to know what kind of fire you're dealing with if you want to fight it, as different fuel sources can greatly change how you extinguish a fire.
How would you know you were dealing with a Class A fire?
A Class A fire has "normal" everyday items as its fuel source. Paper, wood and plastic are common, which is why this type of fire is also one of the most common accidental types of fires.
How does a Class B fire differ from a Class A fire?
Class B fires have liquid or gas fuel sources. Because a flammable liquid is a source for this kind of fire these are usually, but not always, the kinds of fires you'd be more likely to find in an industrial setting.
What is the most distinguishing feature of a Class C fire?
A class C fire is a fire that had some kind of electrical components, such as faulty wiring or an overheated engine. To fight these kinds of fires, you need to make sure you cut the power source.
What somewhat unusual fuel source are you going to have if you're dealing with a Class D fire?
Class D fires have combustible metals as their fuel source. Obviously, not many metals are going to burn very often, but some will at the right temperature, like magnesium or aluminum. These fires should not be fought with water, which can make the situation much worse.
The fifth type of fire is a Class K fire and is not uncommon in homes. What's the fuel source?
Even though a Class B fire uses a liquid as a fuel source, Class K fires got their own classification for being unique enough to merit special attention. These fires are the products of burning cooking liquids like vegetable oil.
Flash point refers to the temperature at which a compound will ignite. What does the flash point of a liquid have to be for it to be considered combustible?
A combustible liquid has a flash point at or over 100 F. Anything that ignites lower than that temperature is considered a flammable liquid as opposed to a combustible one.
At the scene of a blaze, during what time period does the fire department have authority over the area?
Though the fire department may continue investigating a fire long after it ends, the scene itself is under the authority of the department only until all firefighters have left the area.
What's the reason that you need more energy to get water to travel through a long length of hose compared to a short length of hose?
Due to the friction of the water in a length of hose, you need more power pushing that water out of a longer hose than a shorter one. That's very relevant when you're fighting a fire, as the force from a longer hose will be diminished.
How much heat energy (per pound) is contained in a fuel like wood, measured in British Thermal Units (BTUs)?
This one is a bit tricky, since different woods will obviously have measurements for heat energy but most firewood you're likely to use in your day-to-day life probably ranks between 5,000 and 7,000 BTUs per pound.
What does the abbreviation S.C.B.A. stand for?
The self-contained breathing apparatus is the breathing system that allows a firefighter to handle breathing in conditions with low oxygen or toxic fumes in the air.
Heat can travel in the form of radiated heat, like infrared or ultraviolet rays. How fast do those rays travel?
These kinds of rays travel at the speed of light because they're thermal radiation and essentially are light. Other kinds of heat like convection and conduction are much slower.
In the course of rescue work as a firefighter, you may need to use a hydraulic tool to extricate someone from a car wreck. What's that tool called?
Possibly the most famous tool in emergency car wreck response, the Jaws of Life operate very much like a giant, metal bird beak cutting into or prying apart smashed metal to allow access to a damaged vehicle.
Not everyone knows that the Jaws of Life is more of a colloquial name. What is the proper name of that tool?
The Hurst Tool was named for its inventor George Hurst in 1961, replacing normal saws that had been used previously in serious car accidents.
What is someone talking about when they mention the "super scooper?"
The "super scooper" refers to a Canadian CL-415 Bombardier Aircraft which can carry over 3,000 gallons of liquid to be dumped over a fire.
What do you call it when the heated gases in a room that is on fire explode after additional oxygen is introduced?
When the oxygen level in a room gets low as a result of being consumed in the fire, opening a window or a door and providing a sudden influx of new oxygen can create a massive explosion known as a backdraft.
How is a flashover different from a backdraft?
A flashover and a backdraft may look a lot alike, but a flashover occurs when the thermal radiation in a room radiates back on all the contents of the room, causing everything to ignite, as opposed to backdraft which requires oxygen to be added.
Many fires will have a FAST team on site. What does FAST stand for?
The Firefighter Assist and Search Team are a group of firefighters whose job it is to assist other firefighters in need should they become trapped or require assistance on the scene during a fire. They rescue the rescuers.
Who are you going to see wearing a white helmet at the scene of a fire?
Things can get hectic during a fire, so different ranking firefighters have different helmets to help people identify them more easily. The chief officers, the highest-ranking of all, will be wearing white.
When responding to an emergency call, should firefighters in the truck be wearing seatbelts?
Even though firefighters may be able to drive faster to get to an emergency, they still need to follow basic safety precautions like wearing seat belts.
What does it mean if a hose is "charged?"
A charged hose is one that has been pressurized and is primed and ready to be used for firefighting. A hose that has not been pressurized will not be much good at the spur of the moment when it's needed.
How often do most fire departments recommend that homeowners change the batteries in their smoke detectors?
Though it's true some may recommend only once a year, most often it's recommended to be done twice a year, typically when the clocks get changed for daylight saving time to make it easier to remember.
How much weight do you need to be able to carry when hauling your full firefighter gear?
Typical firefighting gear will weigh in around 65-75 pounds. When this gets soaked with water it can weigh a lot more, which is part of the reason it's so important for firefighters to be in peak physical condition.
There are several types of trucks firefighters can use in their jobs. What is a quint truck?
A quint truck, or quintuple combination pumper, can serve as both an engine and a ladder truck. The "quint" part refers to 5 functions it can perform including a pump, water tank, ladders, hoses and rescue equipment.
What do you call the person whose job it is to take responsibility for the situation and ensure the safety of all personnel?
The Incident Commander is an integral part of organization for firefighting. An Incident Commander must be able to delegate responsibility and keep track of subordinates to ensure safety and smooth operations in order to minimize risk at all times.
What is a PASS device?
The Personal Alert Safety System is an alarm that all firefighters should be equipped with. It can sense when a firefighter is exposed to a rapid temperature increase or has remained still for an extended period and may require assistance.
Why would air horns begin to sound while firefighters are in a building?
When firefighters are in a building and it becomes clear that the structure has become so damaged that a collapse is imminent, air horns can signal those inside they need to leave immediately.
As a firefighter, you will be required to medically assist people. What is the normal breathing rate for an adult?
The normal respiration rate for an adult is around 12 to 20 breaths per minute. Anything lower or higher than that should be cause for alarm.
According to NFPA standards, what is the maximum number of people a supervisor should manage at the scene of an emergency?
The National Fire Protection Agency limits the number of subordinates one supervisor can manage to 7. This is a safety issue, as having too many people in a tense and dangerous situation can obviously lead to oversights and accidents.
What are the respiratory dangers that need to be accounted for in any fire situation?
There's no one single danger when breathing in the air during a fire, as fumes from toxic substances, a lack of air and smoke inhalation can all cause serious health issues and death.
Why is water a bad choice for fighting an electrical fire?
The big danger with water around electricity is the fact water can conduct electricity. If firefighters are standing in pools of water, they run the risk of being electrocuted.
What would be the best way to put out a Class D fire?
Because Class D fires are fueled by metals, many of which can be very reactive, water would actually make them worse. A dry powder extinguisher will smother the fire and also absorb the heat.
If you're offering medical attention to someone, what should their pulse rate be, assuming they're an otherwise healthy adult?
A normal, healthy heart rate should be around 60 to 100 beats per minute. A person very likely requires medical attention if they fall below or above that range.
Firefighting has been a part of human history since fire itself was first discovered. It's an awesome force that even after thousands of years we still haven't fully managed to master. Because fire can be so unpredictable and so dangerous, we'll very likely always have to rely on people skilled enough and brave enough to rush into the inferno when duty calls. It's pretty impressive and awe-inspiring that so many people are willing to risk their lives in such a real way to help others in the face of the fury of nature.
Firefighting has come a long way from the simple roots of people doing their best to splash water on a blaze in the hopes of keeping it under wraps. Technology and training have made an incredible difference in how we fight fires and ultimately save lives. The people who step up to take on the responsibility of handling fires have to not just be physically ready for the demands of the job but mentally as well. One of the most important tools for determining who is ready is a simple test. If you want to know if you can stand toe-to-toe with the firefighting elite, try our practice questions and see how you do!
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