Which class of standpipe is specifically designed for firefighting use by trained personnel?

Class I standpipes are specifically designed for firefighting use by trained personnel, providing a 2.5-inch outlet suitable for use with fire hoses. This design caters to professional firefighters who have the training and equipment to operate the system effectively. In contrast, Class II standpipes are intended for use by the building occupants and offer a 1.5-inch outlet, which can be used by individuals who may not possess specialized firefighting training. Class III combines features of both Class I and Class II, serving both trained personnel and the general public, thus diluting its specific intent geared solely toward trained firefighters. Therefore, Class I is distinct in its exclusive focus on professional firefighting efforts.