Which of the following best describes a portable fire extinguisher?

A portable fire extinguisher is defined as a device that contains a specific agent such as liquid, powder, or gases designed to suppress fires. This definition underlines the primary function of fire extinguishers, which is to combat various types of fire through the use of these agents. Portable fire extinguishers are designed to be easily accessible and usable by individuals in emergency situations, making them a crucial component in fire safety preparedness.

The characteristics that define a portable fire extinguisher include its ability to be transported and utilized in various environments, its immediate availability for emergency response, and its specific design to handle different classes of fires based on the agent it contains. This capability distinguishes it from systems that are fixed installations or automatic fire suppression systems, which activate without human intervention and are not designed to be moved.

The other choices reflect different aspects of fire safety or equipment but do not capture the essence of what a portable fire extinguisher is. For instance, a fixed installation for fire control implies a permanent setup rather than a movable device. Thus, identifying a portable fire extinguisher correctly encompasses its purpose and functionality in fire suppression situations.