Appendix C – Glossary

accelerators
quick opening device that speeds up the trip action of a dry pipe valve
air dryer
a system used to remove the water vapour from compressed air for use in dry preaction and dry–pilot systems
backfill
earth, soil or screened gravel (aggregate) used in proper placement to bury underground piping
cathodic protection
a method used to reduce or prevent corrosion caused by electrolysis in underground piping and tanks
combined dry pipe/preaction system
dry pipe system that employs a supplemental detection system
cross–connection control
the use of backflow preventers that prevent potentially contaminated water from flowing back into the potable water supply
deluge system
a system with open sprinklers installed that will discharge water from all sprinklers simultaneously once the automatic water flow control valve opens
dies
equipment used to cut external threads in rod or pipe
dry pipe system
a sprinkler system normally filled with pressurized air or nitrogen used in areas subjected to freezing conditions
escutcheon (plate)
plates or other devices used to cover the annular space around a sprinkler which is designed to maintain the position of the sprinkler in the centre of the penetration
excess pressure pump
automatic water pump that maintains a wet system pressure greater than the highest anticipated supply pressure to prevent false alarms
fire pump assembly
water pump designed to supply or supplement flow and pressure dedicated to fire protection
flow switch
a device that will initiate a water flow alarm upon a water flow condition
flushing connection
a connection used to flush debris from piping systems
grade (pitch)
the slope of a pipe or trench, usually expressed as a ratio of rise (change in elevation) to run (change in distance)
grooving (of pipe)
the process in which a groove is cut, pressed or rolled into a pipe around its outside circumference
hanger assemblies
components that provide overhead support for pipe and piping components
sprinkler guards
a device installed on sprinklers to limit mechanical damage
heat-actuated device (HAD)
heat–activated device, triggered when a specified temperature or rate of increasing temperature is detected
lay down
a predetermined area where material is stored
mark–ups / as–built drawing
a revised set of drawings submitted by a contractor upon completion of a project that reflect all changes made in the specifications and shop drawings during the construction process
preaction systems
a sprinkler system employing automatic sprinklers that are attached to a piping system that contains air that may or may not be under pressure with a supplemental detection system installed in the same areas as the sprinklers
pressure switch
a device used for monitoring high or low pressure in piping system
pump room
also called pump house. A designated area or room in a building or outside a building that contains a fire pump and its components
reaming
a process to restore the pipe to its original inside diameter, usually by removing the internal burr or flare formed when the pipe was cut
seismic/sway bracing
a restraining system that prevents differential movement between the pipe and the building structure during an earthquake
shop drawings
a drawing or set of drawings produced by the contractor, supplier, manufacturer or subcontractor for the purpose of installing, fabricating and bidding
sleeve
a device used to provide an unimpeded path through a building penetration
sling
a metal or synthetic device used to support a load for the purpose of lifting or relocating
suppression systems
a system that causes a sharp reduction in the heat release rate of a fire that prevents its regrowth by means of direct and sufficient application of fire protection media directly to the burning surface
standpipe system
a system of either vertical or horizontal pipe that provides a water supply to facilitate manual firefighting within a building
tamper switch
device which monitors the opening or closing of a valve by sounding a signal in the fire alarm panel
thrust block
concrete restraint cast in place at a critical point in underground piping installations, in order to prevent hydraulic pressure from moving or separating pipe joints
trim
piping and components attached to valves, tanks, and pumps to facilitate proper operation
valves
device placed in a piping system to control or direct the movement of fluid
water motor gong
a water–operated local audible alarm
wet pipe system
a sprinkler system employing automatic sprinklers attached to a piping system containing water and connected to a water supply so that water discharges immediately from sprinklers opened by heat from a fire