Associate Safety Professional Practice Exam

What happens in a dry-pipe system when the pressure drops?

1. Water is released immediately

2. Air pressure increases

3. Water is released when the sprinkler head opens

4. Water floods the entire system

The correct answer is: Water is released when the sprinkler head opens

In a dry-pipe sprinkler system, the pipes are filled with pressurized air rather than water. This air pressure keeps a valve (the dry-pipe valve) closed, preventing water from entering the sprinkler pipes. When a fire occurs and a sprinkler head is activated, it opens, leading to a reduction in pressure within the system. As a result, the dry-pipe valve opens and water is allowed to flow into the pipes, which then comes out of the opened sprinkler head. The correct answer highlights that water is released specifically when the sprinkler head opens, which is central to the operation of dry-pipe systems. This mechanism ensures that water only fills the system and is dispensed in response to an actual fire event, minimizing the risk of water damage from accidental activation. While other choices suggest events that don't accurately reflect the functioning of dry-pipe systems, the core principle remains that activation of a sprinkler head leads directly to the release of water, making the chosen answer the most accurate representation of this specific fire protection technology's operation.