This system is another type of dry-pipe sprinkler system where water flow from the alarm valve into the pipe system is initiated by either the opening of a sprinkler or the activation of an automatic detection system. Unlike other systems, the opening of the alarm valve is caused by a drop in pressure inside the pipe, regardless of the response of detectors.
A non-interlocked dry-pipe sprinkler system can be used in places where a rapid fire spread is expected, and it can replace accelerated or non-accelerated dry-pipe systems. The activation method is determined based on the preferred detection system used in the area, and it can be pneumatic or pneumatic/electric.