Book 100 Ch 8 Water Systems Flashcards
Pre-1960 height limited on buildings to
150’ or approximately 13 stories, mainly due to the threat of earthquakes
Dry standpipe risers are depending on the building height are how big and flow how much?
4” to 6” diameter pipe and must flow 500 gpm per riser.
Inlets?
(2) 2 1/2” inlets if 4-5 stories
(4) 2 1/2” inlets if 6 stories or more
Outlets for dry standpipes are provided at
every floor level and roof landing of required enclosed stairways, fire escapes and smoke towers except the first floor
Outlet are located based on the requirement that
every point within the structure must be reachable by a 30’ stream of water from a nozzle attached to 100’ of hose.
Class II are required on buildings
three or more stories (four or more stories after 1983)
Class II is directly connected to a ____ and equipped with _____
a water supply / 1 1/2” outlet with hose and nozzle
Water supplied to Class II from ___
Domestic water system / Gravity Feed or Pressurized tanks and domestic water system
Wet standpipe risers are
1 1/2” or 2 1/2” depending on the height of the building and year or construction.
Flow requirements for wet standpipes at roof outlets: Prior to 1948
8 PSI flowing 20 GPM
Flow requirements for wet standpipes at roof outlets: 1948 to 1959
12 PSI flowing 35 GPM
Flow requirements for wet standpipes at roof outlets: 1960 to 1970
15 PSI flowing 35 GPM
Flow requirements for wet standpipes at roof outlets: 1970 to present
30 PSI flowing 35 GPM
1960 to 1974 height restriction?
no maximum height.
1960 to 1974, Changes in these water systems were necessary due to
height, center core construction and sealed buildings.
After 1960, standpipes were required in the
stairshafts
If the height of the buildings exceeded 150’ standpipes were ____
charged with water and fire pumps were required in the building to provide pressure at the outlets.
Combination standpipe systems are directly connected to a ___ and equipped with _____
water supply / both 1 1/2” outlets (2 1/2” outlet with a 1 1/2” reducer) with hose and nozzle attached for occupants and 2 1/2” outlets for FD
Combination standpipe system: May have 100’ of single jacketed, unlined 2 1/2” hose with a 1” tip attached to 2 1/2” outlets on each floor above the ____
5th floor
Combination standpipe system: Two separate sources of water supply are required = Primary is _____
Secondary ______
Primary is domestic
Secondary is LAFD
Combination standpipe system: As the water is supplied from the domestic system, _____ are required to keep the firefighter water from _____
two back flow clapper valves / flowing back into and contaminating the domestic water system.
Combination standpipe system: ______ will be found on each side of the back flow valves so that maintenance work can be done on the valves.
Outside stem and yoke
Combination standpipe system: ______ will also be found on each side of the fire pumps for maintenance purposes
Outside stem and yoke
Combination standpipe system: To keep the water from flowing back down the standpipe when the fire pump is shut off, a ____ is placed in the piping on the pressure side of the pump just ahead of the OS&Y
a check valve.
Combination standpipe system: Jockey pumps are normally installed to make up ____
minor leakage rates in system pressure.
Jockey pumps prevents the fire pumps from
continually starting and stopping due to minor fluctuations in the system pressure
Combination standpipe system: inlets?
(4) 2 1/2”
(6) 2 1/2” if 3 or more risers
Combination standpipe system: Fire pumps?
Diesel or electric, Jockey pump to maintain static pressure
Combination standpipe system: On site water?
Not required
Combination standpipe system: Risers? and flow
6” and must flow 1000 GPM per riser
Combination standpipe system: flow required at each outlet?
300 GPM
Combination standpipe system: After water leaves the fire pump, the piping will split to supply the standpipe in each stairshaft, the standpipe located in each stairshaft will have an
OS&Y at the base of the riser, If one riser were to break, the OS&Y valve can be shut off for that riser and water will still be available from the riser in the other stairshaft