Red Seal Sprinkler Fitter Practice Exam 2026 – Complete Prep Guide

The wet system is a widely recognized type of fire sprinkler system that is characterized by its use of water stored in the piping. In a wet system, the pipes are always filled with water and are under pressure, which means that when a sprinkler head is activated due to heat from a fire, water is immediately discharged to suppress the flames. This system is particularly effective in environments where freezing temperatures are not a concern, as it ensures a swift response to a fire event.

In comparison, the other options are not conventional types of fire sprinkler systems. An underground system typically refers to the water supply infrastructure that supports fire protection systems rather than the actual sprinklers themselves. Portable systems, while designed for temporary use, do not form a standard category of fire sprinkler systems as they may not provide the reliability or coverage required for permanent installations. Manual systems rely on human intervention to operate, lacking the automatic response that a wet system provides, which is a key feature for fire suppression systems to effectively protect properties.