What is a transfer main that is supplied by the riser or cross main called?

A transfer main that is supplied by the riser or cross main is referred to as a feed main. This term is used in fire protection and sprinkler systems to describe the pipe that carries water from a main supply line or another source to the areas where it is needed for distribution. The feed main delivers water to the various branches of the system, ensuring that adequate pressure and volume are maintained for effective operation.

Understanding the concept of a feed main is crucial for a sprinkler fitter, as it connects the primary water supply to the various components of a fire protection system. The feed main plays a vital role in managing the flow and distribution of water, thus enhancing the overall efficiency and effectiveness of the sprinkler system during a fire event.