Standpipe systems Flashcards
Standpipe class 1
For use by fire department and those trained in handling heavy fire streams - high flows and pressures.
equipped with only a 2 1/2” outlet
shall be capable of furnishing the effective fire streams required during the more advanced stages of fire on the inside of buildings or for exposure fire protection
Typically for the purpose of fire extinguishment
Standpipe class 2
For use primarily by the building occupants until the arrival of the fire department
1 1/2” hose outlet
for the control of incipient (the initial stage) fires by the occupants of the building
It is not designed for fighting fires
Standpipe class 3
Used by fire departments and/or those trained in handling heavy hose streams
shall be capable of furnishing class 1 and class 2 service
Can have 1 1/2” outlet and 2 1/2” outlets, or a 2 1/2” outlet with an adapter
Exceptions
light hazard hose can be smaller than 1 1/2”
when the building has sprinklers: class 2 personnel do not require training
travel distance 130’ without sprinklers / 200’ with sprinklers
Standhose system types
automatic wet, combined, manual wet, automatic dry, semi-automatic dry, manual dry
automatic wet
standpipe is filled with water
combined system
supplies hose connections and automatic sprinklers
manual wet
water is in the pipe but relies on the FDC
automatic dry
dry pipe system for trained personnel only
semi-automatic
admits water to the system through manual operation of approved remote control devices located at each hose station
manual dry
no water supply, relies on FDC
true or false. Every standpipe system has to be hydraulically calculated.
true.
pipe scheduled systems may still be in service.
Class 2 max 400’
class 3 max 275’
class 1 + class 3 pipe sizes
minimum standpipe size 4”
combined systems, partially sprinklered = 6”
branch lines not less than 2 1/2”
class 2
hydraulic calculations and pipe size based on 100gpm at the hydraulic most remote connection at the required pressure 7.8.1
Standpipe pressures
Pressures
• Standpipes shall supply - Minimum Pressure
• 65 psi (4.5 bar) at the topmost 1 ½”outlet Class II
• 100 psi (6.9 bar) when it’s 2 ½” Class I & III
- Standpipes shall supply - Maximum Pressure
- 100 psi for Class II – 1 ½”
- 175psi for Class I and III – 2 ½”
• Maximum system pressure = 400psi (2019 edition is
400psi)
Flows
Class I and Class Ill services, each standpipe shall be sized
for a minimum flow of 500 gpm (1893 L/min)
Designed for a minimum flow of 500 gpm for the first
standpipe plus 250 gpm (946 L/min) for each additional
standpipe.
Minimum total flow
• 1250 gpm (4731 L/min) - unsprinklered
• 1000 gpm (3785 L/min) - buildings sprinkled throughout.
For buildings that exceed 80,000 ft.²(7432m2) per floor
• the minimum flow rate for the additional standpipes shall be
• 500 gpm (1893 L/min) for the second standpipe
• and 250 gpm (946 L/min) for the third standpipe
Combined systems
Comply with NFPA 13 for sprinklers and NFPA 14
regarding size of vertical risers (standpipes) and water
supplies
• For fully sprinklered systems demands from 13 and 14
are compared and the final system demand is the
higher of the 2
• Consider the hose stream allowance of 13 = 50gpm/
hose valve to a maximum of 100 light hazard, 250
ordinary and 500 extra hazard
Multiple zones/Multiple pumps
Where pumps supplying two or more zones are located at the same level, each zone shall have separate and direct supply piping of a size not smaller than the riser which it serves.
• At least two lines shall be provided between zones; one of these lines shall be arranged so that supply can be automatically delivered from the lower to the higher zone.
*Supply must be maintained for a 30-minute duration
Water Supplies
Acceptable water supplies may be:
• 1. Public waterworks system where pressure and discharge capacity are
adequate.
• 2. Automatic fire pumps.
• 3. Manually controlled fire pumps in combination with pressure tanks.
• 4. Pressure tanks.
• 5. Gravity tanks.
• 6. Manually controlled fire pumps operated by remote control devices at each
hose station.
Locations
Class 1 and 3 hose connections:
must be within 150’ for unsprinklered
200’ for sprinklered
class 2 within 130' 120' if < 1 1/2" hose
streams must be supplied to all rooms, ie. around the partitions
standpipe risers and horizontal standpipe runs:
shall not pass-through hazardous areas
shall be located so they are protected from mechanical and fire damage
Dry standpipes shall not be concealed in building walls or built into pilasters
Locations of hose connections
*3’-5’ above the floor
• At the main floor landing in exit stairways
• On each side of the wall adjacent to the exit openings of horizontal
exits.
• In other than covered mall buildings,
• in each exit passageway at the entrance from the building areas into the
passageway
• In covered mall buildings,
• at the entrance to each exit passageway or exit corridor,
• at the interior side of public entrances from the exterior to the mall.
• At the highest landing of stairways with stairway access to a roof
• On roofs with a slope of less than 4 in 12 where stairways do not
access the roof.
Class 2 hose lengths
Class II systems
• If 1 ½” hose is provided within 130ft
• If < 1 ½” hose is provided within 120ft
• Class II hose stations are generally in the corridor,
whereas Class I & III are in the stairwells
Standpipe locations
Standpipes are required in exit stairways
• Where the building is protected throughout by an
approved automatic sprinkler system
• Class II hose stations for use by trained personnel shall not be
required, subject to the approval of the local fire department
and the AHJ
• provided that each Class I hose connection is 21/2 in. (65 mm)
and is equipped with a 21/2 in. × 11/2 in. (65 mm × 40 mm)
reducer and a cap attached with a chain.
Listed equipment + hose connections
All devices and materials used in standpipe systems shall
be listed.
• Exception - devices that do not affect system
performance are not required to be listed (drains, signs).
• Hose connections for use by trained personnel
• may be equipped with not more than 100 ft. of lined fire hose.
Any unlined hose shall have a drip connection to prevent any
slight leakage entering the hose.
• Each hose connection for dry standpipes having no
permanent water supply shall be provided with a
conspicuous, durable and permanent legible sign reading
• “Dry Standpipe for Fire Department Use Only.”
