#1 Fire Extinguisher, Fire Sprinkler and Fire Protection Service Company of Southern California.

red fire truck logo
Call us first!
red fire truck logo
Call us first!

What Are the 5 Main Components of Fire Extinguishers?

There are five main components of fire extinguishers. All those components have to meet specific legal requirements, similar to how every fire extinguisher has to undergo regular inspection. Even though most fire extinguishers don’t have expiration dates, they can still go bad. 

The quality of the internal parts of the fire extinguisher has to be really high in order for it to do what it was designed to do in the best possible way. So, before you start searching for fire extinguisher companies in Orange County and the rest of Southern California, take a look at what makes up an extinguisher.

What is inside a fire extinguisher?

fire extinguisher companies in Orange County

Every single part of a fire extinguisher plays a key role in eliminating the elements of the fire triangle. The proper functioning of all the components is what allow a fire extinguisher to discharge chemicals and stop or suppress a fire.

Being familiar with the inner workings of a fire extinguisher allows you to learn more about how it functions. However, it can also help you use it more adequately should the need arise. Here are the five main components of a fire extinguisher. 

Cylindrical tank

The largest and the most recognizable component of a fire extinguisher is certainly the red cylindrical tank that houses the chemicals used to put out fires. Not all fire extinguishers are red, but they tend to be. 

The cylindrical tank has a flat bottom, so that the extinguisher can be placed on the floor, and a top shaped like a dome. The propellant and the extinguishing agent are inside this tank. The tank is made of metal.

Valve assembly

Valve assembly regulates and controls the flow of the extinguishing agent inside the tank. This competent of a fire extinguisher is comprised of several subcomponents:

  1. Body – The machined body of the valve assembly is usually made of a metal bar shaped by a lathe. The body of the valve assembly on some lower end fire extinguishers is made of injection-molded plastic. 
  2. Handle – The handle allows you to pick the extinguisher up and carry it to the place affected by the fire.
  3. Pull pin – The pull pin prevents accidental discharge of the extinguishing agent. You first have to remove the pull pin before you can actually use the fire extinguisher.
  4. Tamper seals – Tamper seals are made of plastic, and they keep the pull pin in place. 
  5. Release lever – Pressing the release lever allows the extinguishing agent to begin discharging.
  6. Dip tube – This tube goes inside the cylinder tank and it draws the agent up when you press the release lever.
  7. Pressure gauge – Stored pressure extinguishers contain a gauge that measures the pressure of the chemicals hosted within the tank.

Nozzle and hose

These two components direct the extinguishing agent as it starts leaving the cylinder tank. Some extinguishers do not have a hoze, and they only employ a nozzle to distribute the extinguishing agent.

However, fire extinguishers that exceed 5lbs in weight typically tend to have a hose as well, as it allows you to change the direction of the flow more easily. 

Extinguishing agent

The extinguishing agent is a vital component. This chemical substance is what actually suppresses or puts out the fire. Depending on the class of a fire extinguisher, the type of the extinguishing agent will vary.

Some extinguishing agents are suitable for taking out electrical fires, while others work better for combustible and flammable liquids. Consequently, the extinguishing agent can be dry chemical mono ammonium phosphate, or a blend of potassium acetate and potassium citrate.


Propellant is a gas that expels the extinguishing agent from the extinguisher. Depending on the type of fire extinguisher, the propellant has a different location:

  • Stored pressure extinguishers house the propellant together with the extinguishing agent.
  • Cartridge-operated extinguishers store the propellant within a separate cartridge. When you activate the fire extinguisher, this cartridge gets punctured to provide the necessary pressure for the extinguishing agent.

Contact a reputable company that sells and services fire extinguishers in Orange County!

What is inside a fire extinguisher

If you’re a business owner looking to outfit your offices with quality fire extinguishers, Red Truck Fire & Safety is the leading provider of quality products that meet the required regulations.

We offer fire extinguishers of all classes and for many different uses, so no matter what you’re looking for, we have it. We make fire safety a top priority. Contact us today!

Contact Us