Does a fire alarm set off the sprinkler system?

Answer 1

Most standard fire sprinklers are activated by heat. There's a small bulb of liquid that keeps the water back in the pipes before a fire begins. When a fire breaks out, that liquid will heat up and eventually cause the bulb to burst, releasing the water from behind it.

Answer 2

Fire and smoke, of course! Also, many fire alarms have manual pull stations and other sensors. For example, water flowing in the sprinkler system, someone opening a fire extinguisher box or AED enclosure, improperly adjusted or maintained sensors can all set off the alarm.

Answer 3

Usually, yes.

There is a loss of static pressure on the lines and the alarm is activated, or there may be another type of flow detector in the supply line.

NFPA Fire Alarm Code requires that any sprinkler activation in a building with a fire alarm system also triggers the fire alarm.

Answer 4

Generally, no, a fire alarm will not set off sprinklers, each of which is separately triggered by heat.

However, there are certainly two specific kinds of sprinkler systems, known as "deluge" sprinklers and "pre-action systems", in which one or more smoke or heat sensors can, in fact, pressurize the system and flow water though any open sprinkler heads. In a deluge system, the sprinkler heads do not include heat-activated valves. In a pre-action system, water will only flow out of a sprinkler head if its thermal valve has also opened.