What is the expellant gas commonly used to expel extinguishing agents from portable fire extinguishers?

What is the expellant gas commonly used to expel extinguishing agents from portable fire extinguishers?

• A. Proportioning
• B. Expellant Gas
• C. Head Pressure
• D. High Rise Building

Answer: (B)

In portable extinguishers, the extinguishing agent is pushed out of the cylinder by a propelling gas. This expellant gas provides the forces needed to eject the agent through the nozzle when the handle is operated. The term Expellant Gas names this propellant itself—the gas used to drive the extinguishing agent out. Depending on the extinguisher type, the expellant can be compressed air or nitrogen, or, in extinguishers where CO2 is the agent, CO2 serves as both the agent and the expellant. The other options refer to different concepts and don’t describe the gas that actually pushes the agent out, which is why the expellant gas is the best answer.

In portable extinguishers, the extinguishing agent is pushed out of the cylinder by a propelling gas. This expellant gas provides the forces needed to eject the agent through the nozzle when the handle is operated. The term Expellant Gas names this propellant itself—the gas used to drive the extinguishing agent out. Depending on the extinguisher type, the expellant can be compressed air or nitrogen, or, in extinguishers where CO2 is the agent, CO2 serves as both the agent and the expellant. The other options refer to different concepts and don’t describe the gas that actually pushes the agent out, which is why the expellant gas is the best answer.