What classification of fire apparatus is specifically designed for heavy technical rescues?

The classification of fire apparatus specifically designed for heavy technical rescues is termed as a special service vehicle. These vehicles are equipped with specialized tools and equipment required for complex rescue operations, such as extricating individuals from confined spaces, performing high-angle rescues, or conducting water rescues.

Special service vehicles typically carry gear that may include hydraulic rescue tools (such as the "Jaws of Life"), medical equipment, and other resources tailored for technical rescue scenarios. Their design focuses on providing versatile support for emergency situations beyond basic firefighting, making them essential in incidents that demand specialized skills and equipment.

In contrast, a pumper is primarily used for delivering water and firefighting capabilities; a mobile water supply refers to vehicles that transport large quantities of water for firefighting purposes but lack the specialized resources for rescue operations. A tank truck is designed to carry water or other liquids but does not have the necessary tools and equipment for heavy technical rescues. Thus, the special service classification is the most appropriate choice for apparatus focused on heavy technical rescues.