Standpipe Design Question
Standpipe Design Question
(OP)
Alright, I live in New York City & I have inspected many residential buildings that have gravity tanks and DO NOT HAVE FIREPUMPS.
15fls x 8 ft = 120
Lobby =12 ft
basement =12 ft
tank above roof = 15ft
(17) 16 inch slabs =272 inch / 12in = 22.6 ft
=181 ft
181 ft x 0.433psi = 78.373psi
water reserve is 15,000 Gpm
How does the system get its required pressure demand to meet NFPA 14 code in such a situation?, in fact NYC allows 65 psi.
I ask because once Hazen williams formula is used and equivalent pipe chart, psi will drop for (pipe fittings) elbows, OS&Y Valve, Check Valve, OS&Y Valve), Mech-Tee and the actual 2 1/2 house valve its self.
P.S. Thank you for your time.
15fls x 8 ft = 120
Lobby =12 ft
basement =12 ft
tank above roof = 15ft
(17) 16 inch slabs =272 inch / 12in = 22.6 ft
=181 ft
181 ft x 0.433psi = 78.373psi
water reserve is 15,000 Gpm
How does the system get its required pressure demand to meet NFPA 14 code in such a situation?, in fact NYC allows 65 psi.
I ask because once Hazen williams formula is used and equivalent pipe chart, psi will drop for (pipe fittings) elbows, OS&Y Valve, Check Valve, OS&Y Valve), Mech-Tee and the actual 2 1/2 house valve its self.
P.S. Thank you for your time.





RE: Standpipe Design Question
Not even close.
For 65 psi the bottom of the tank would have to be at least 65/.433=151 feet above the highest connection and that doesn't take into consideration any friction loss through pipe or valves.
RE: Standpipe Design Question
A gravity tank feeding a single building or multiple buildings and there is no Firepump..
How would the system get the required pressure or is there something im missing?
RE: Standpipe Design Question
RE: Standpipe Design Question
RE: Standpipe Design Question
I have those certifications, I have read that book multiple times once I noticed this scenario at places I inspect...i suspect the buildings systems are grandfathered in...Im asking because I dont wanna make a stink about it at work and its something perfectly normal.
RE: Standpipe Design Question
If so how are you seeing the pressure and flow met???
Hydrostatic test (5 years) See Fire Department Code section 905.12.1
Flow test
Upon order of the commissioner, but at least once every 5 years, the standpipe system shall be subjected to a hydrostatic pressure test and a flow test to demonstrate its suitability for department use. These tests shall be conducted in compliance with the requirements of the rules and shall be conducted at the owner's risk, by his or her representative before a representative of the department.
(3 years) See Fire Department Code section 905.12.2
At least once every three (3) years, standpipe systems with pressure reducing devices installed shall be flow tested with a minimum actual flowing discharge of 250 gpm. These tests shall be conducted by a master fire suppression contractor who shall provide the Department five (5) business days notice of the date and time of the test. The Department may witness these tests at its discretion.
RE: Standpipe Design Question
RE: Standpipe Design Question
RE: Standpipe Design Question
RE: Standpipe Design Question
Travis Mack
MFP Design, LLC
www.mfpdesign.com
"Follow" us at https://www.facebook.com/pages/MFP-Design-LLC/9221...
RE: Standpipe Design Question