ANSWERS GUARANTEE A+
✔✔Supervisory signal-initiating device - ✔✔An initiating device, such as a valve
supervisory switch, water level indicator, or low-air pressure switch on a dry-pipe or pre-
action sprinkler system, that triggers a supervisory signal.
✔✔Testing - ✔✔A procedure used to determine the status of a system as intended by
conducting periodic physical checks on water based fire protection systems such as
waterflow tests, fire pump tests, alarm tests, and trip tests of dry pipe, deluge, or
preaction valves. These tests follow up on the original acceptance test at intervals
specified in the appropriate chapter of NFPA #25, 2002 edition.
✔✔Upright Sprinkler - ✔✔A sprinkler designed to be installed in such a way that the
water spray is directed upwards against the deflector.
✔✔Water Spray Fixed System - ✔✔A special fixed pipe system connected to a reliable
fire protection water supply and equipped with water spray nozzles for specific water
discharge and distribution over the surface or area to be protected. The piping system is
connected to the water supply through an automatically or manually actuated valve that
initiates the flow of water. An automatic valve is actuated by operation of automatic
detection or manual release equipment installed in the same areas as the water spray
nozzles. (In special cases, the automatic detection system may also be located in
another area.)
✔✔PREACTION SPRINKLER SYSTEMS - ✔✔designed for situations where there is
danger of serious water damage. Water damage is usually caused by damaged
sprinklers or broken piping. Under normal conditions there is no water in the piping. The
air in the piping may or may not be is under pressure. A preaction valve prevents the
water from entering the system. The valve is automatically opened when a fire detection
system discovers that there is a fire or smoke condition. The preaction valve is tripped
by the fire detection system before any of the sprinkler heads open. A supervisory
device signals when the valve is opened. The preaction valve can also be operated
manually.
✔✔DELUGE SPRINKLER SYSTEMS - ✔✔equipped with open sprinkler heads
designed to wet down an entire area involved in a fire. This system is needed when
there is danger of a fire rapidly spreading throughout the building. The deluge system
will slow down the spread of the fire. Deluge systems are suitable for hazardous
occupancies. This includes buildings in which flammable liquids or other hazardous
materials are handled or stored.
The sprinkler heads in the deluge system are open at all times. Under normal conditions
there is no water in the piping. The air in the piping is not under pressure. A closed
control valve prevents water from flowing into the system. A fire detection device
automatically opens the control valve when a fire is identified. A supervisory device
, signals when the valve is opened. When the valve is opened water flows into the
system. The water is then discharged out all of the sprinkler heads. The water control
valve may also be opened manually.
✔✔NON-AUTOMATIC DRY SPRINKLER SYSTEMS - ✔✔ll pipes are normally dry.
Water is supplied when needed by pumping water into the system through the Fire
Department connection. Some of these systems are supplied by manual operation of a
water control valve and may be equipped with sprinklers with or without fusible links.
There are several non-automatic systems: 1) Perforated pipe systems - a single line of
piping drilled at intervals for water discharge. These systems are usually found in
basements or other areas difficult to reach in fire fighting operations. 2) Open fixed
spray nozzles for transformer vaults or other hazardous areas; 3) exterior exposure
sprinklers (or window sprinklers) use open sprinkler heads to form an external water
curtain on the walls of a building, and 4) Foam supply systems are used for the
protection of special hazardous occupancies.
✔✔Curb Valves - ✔✔Gate valves of the non-indicating type are provided in water
distribution systems. Gate valves allow the sprinkler system to be shut off for repairs or
maintenance. Such valves are normally a non-rising stem type. They are operated using
a special key wrench. A valve box is located over the valve to keep dirt from the valve.
The valve box also provides a convenient access point for the valve wrench to the valve
nut. A complete record should be made for each valve in the system. This record should
include the exact location, the date it was installed, the make, the direction of opening,
number of turns to open, and any maintenance that was performed.
The control valve for the building may also be on the outside wall or attached to an
upright post, known as a post indicator valve (PIV). The building or section of the
building controlled by the valve is usually marked on the post. The position of this valve
(open or closed) is shown through a telltale opening in the post. On some posts, a
padlock must first be opened to release the operating wrench or wheel handle.
✔✔Pumper Connections for Fire Department Use - ✔✔Fire Department connections
must always be accessible. Each connection shall be fitted with a lower check valve.
The lower check valve prevents the backflow of the private water supply into the Fire
Department connection. The figure below shows the main features of a Fire Department
connection.
✔✔Fire Pumps - ✔✔used as a main water supply source for sprinkler systems. They
may also be used in combination with gravity tanks to supply sprinkler system. Fire
pumps are designed to take the water from a supply source and then discharge the
water into the fire protection system under pressure. The amount of pressure with which
the water is discharged from the pump is called the total head. The total head is
measured in pounds per square inch (psi). The higher the psi rating of the pump the
greater the
✔✔Waterflow Alarm Valves - ✔✔The basic design of most water-flow alarm valves is
that of a check valve which lifts from its seat when water flows into a sprinkler system.