The dry pipe system is installed in loading docks, garages, and other areas where water would freeze. The pre-action system is installed in rooms where water damage might cause a problem such as in libraries, computer rooms, and museums. The pre-action system does not contain water in the pipes over these sensitive areas until a detection system activates the water flow. This helps to protect these areas in case a pipe breaks. Just think, sprinklers were invented in 1874 by Henry Parmelee to protect his piano factory and now they are keeping our schools and other buildings safe.
Fire sprinklers have one purpose and that is to keep any fire that starts as small as possible.
They are individually heat-activated and connected to a network of piping with water under pressure. When the heat of a fire raises the sprinklers to its operating temperature, usually between 165 to 175 F, a fusible link or glass bulb will break activating only that sprinkler that is above the fire. Fire sprinklers can save money. I called the county building inspector and he told me that the cost of installing sprinklers in a new building is less than the cost of installing sprinklers in existing buildings. In fact, installing fire sprinklers at the time of construction will often reduce the overall cost of construction materials.