Which class of standpipe system is specifically aimed at aiding trained building personnel?

The class of standpipe system specifically designed to assist trained building personnel is Class II. This type of standpipe system is equipped with 1.5-inch hose connections and is intended for use by occupants of the building who have received training in firefighting but may not necessarily be professional firefighters. The goal of a Class II system is to provide enhanced firefighting capabilities to those who are trained and familiar with basic firefighting techniques, allowing them to effectively combat small fires.

Class II standpipes are commonly found in commercial and large residential buildings, where providing immediate firefighting support to trained personnel can be critical in controlling a fire while waiting for the fire department to arrive. They also typically include the necessary hoses and equipment for trained personnel to use effectively, ensuring they can respond quickly in emergencies.

In contrast, the other classes serve different purposes: Class I is designed for use by professional firefighters, Class III combines features of both Class I and II to serve both trained personnel and firefighters, and "specialized" is not a recognized class under the standard classifications but could refer to specific systems designed for unique applications. Therefore, the focus on aiding trained building personnel aligns specifically with Class II standpipe systems.