What is the primary feature of an Upright sprinkler?

An Upright sprinkler is designed with a specific configuration that includes deflectors which play a crucial role in directing water downward. When activated, the sprinkler head disperses water in a manner that ensures it covers the area immediately below it effectively, allowing for optimal fire suppression. The deflectors help to manage the pattern and distribution of the water, which is essential to maximize coverage and minimize wasted water during an event. This design is particularly suited for environments where installations need to cover open spaces, as the downward projection of water targets the area most likely to require protection in the event of a fire.

In contrast, the other options describe features that do not align with the fundamental operation of an Upright sprinkler. Sprayed water directly to the sides would result in less effective coverage in the critical zone beneath the sprinkler, which is not its intended function. Spraying water upward before it falls is also not characteristic of an Upright sprinkler, as its design aims to direct the water downward efficiently rather than upwards first. Lastly, filling pipes with pressurized air refers to a different element of fire protection systems, typically related to dry pipe systems, which is unrelated to the physical design and function of an Upright sprinkler head.