What is the primary function of a combination wrench in firefighting?

The primary function of a combination wrench in firefighting is to tighten or loosen fasteners. This tool provides the necessary leverage and grip to manipulate nuts and bolts, which are commonplace in various firefighting equipment, vehicles, and apparatus. Proper maintenance of these fasteners is crucial for ensuring that the equipment operates safely and effectively.

Tools like combination wrenches are essential in the maintenance of equipment such as fire trucks, ladders, and hoses. By using these wrenches, firefighters can perform necessary repairs or adjustments quickly and efficiently, which is critical during emergency situations where time is of the essence.

The other options, while related to general activities associated with firefighting, do not accurately represent the specific function of a combination wrench. For example, extinguishing fires involves firefighting equipment like hoses or extinguishers rather than hand tools. Similarly, adjusting hoses typically involves different types of fittings and connectors, and rescue operations focus on life-saving techniques rather than mechanical tool use.