Standpipe Systems
Corpus sync: neutrality remakes, note hygiene, datasheet relocation, transformer-split cross-refs
Showing changes from Rev 3
to Rev 4
in Standpipe Systems.
---
title: Standpipe Systems
…187 unchanged lines
+### The class of standpipe system shall be confirmed against IBC Section 905 and the project program before design begins.
+
```datasheet
label: Standpipe System Class
…6 unchanged lines
default: "Class I (2-1/2 in. outlets for fire-department use)"
```
−### The class of standpipe system shall be confirmed against IBC Section 905 and the project program before design begins.
### A building that requires a Class I standpipe under the code shall not be specified with only Class II hose stations.
…13 unchanged lines
+### The system type shall be selected per NFPA 14 so that the valving, supervisory arrangements, FDC arrangement, and response time when a hose valve is opened match the building configuration, climate, and use case.
+
```datasheet
label: Standpipe System Type
…8 unchanged lines
default: "Automatic-wet (continuously charged, immediate flow)"
```
−### The system type shall be selected per NFPA 14 so that the valving, supervisory arrangements, FDC arrangement, and response time when a hose valve is opened match the building configuration, climate, and use case.
### Automatic-wet systems are continuously charged with water under supply pressure, discharge immediately when a hose valve opens, and are the dominant configuration in conditioned buildings and the standard arrangement for combined sprinkler/standpipe risers. {note}
…12 unchanged lines
### Combined sprinkler/standpipe risers are economical and dominant in commercial high-rise construction because a single riser sized for the standpipe demand can readily satisfy the sprinkler design demand on each floor. {note}
+### A combined riser shall be sized for the greater of the standpipe demand or the sprinkler-plus-standpipe combined demand per NFPA 14 Section 7.10.
+
+### The sprinkler floor control valve assembly on a combined riser shall include a waterflow switch and a tamper switch on the floor branch from the combined riser.
+
+### Combined risers shall not be used where the standpipe demand and the sprinkler demand at different elevations cannot be coordinated within a single hydraulic gradient.
+
```datasheet
label: Standpipe Riser Configuration
…7 unchanged lines
```
−### A combined riser shall be sized for the greater of the standpipe demand or the sprinkler-plus-standpipe combined demand per NFPA 14 Section 7.10.
−
−### The sprinkler floor control valve assembly on a combined riser shall include a waterflow switch and a tamper switch on the floor branch from the combined riser.
−
−### Combined risers shall not be used where the standpipe demand and the sprinkler demand at different elevations cannot be coordinated within a single hydraulic gradient.
−
### Dedicated standpipe risers are used where a combined arrangement is impractical, where the sprinkler and standpipe systems are zoned differently in a tall building, or where the Owner or AHJ requires separation, and they permit each system to be impaired independently for maintenance without affecting the other. {note}
…10 unchanged lines
min: 40
max: 100
− setpoints: [40, 50, 60, 70]
+ setpoints: [40, 50, 60, 70, 100]
default: 40
```
…8 unchanged lines
+### NFPA 14 limits the maximum static pressure in any portion of a standpipe system to 350 psi in standard listed components, and to lower limits at hose connections.
+
```datasheet
label: Maximum System Working Pressure
…8 unchanged lines
```
+### Where the static pressure at any point in the system exceeds 350 psi, the system shall be divided into pressure zones using a separate riser, a fire pump and break tank arrangement, or pressure-regulating devices listed for the higher inlet pressure.
+
```datasheet
label: System Pressure Exceeds 350 psi Without PRVs
…5 unchanged lines
default: "No — system pressure below 350 psi throughout"
```
−### NFPA 14 limits the maximum static pressure in any portion of a standpipe system to 350 psi in standard listed components, and to lower limits at hose connections.
−### Where the static pressure at any point in the system exceeds 350 psi, the system shall be divided into pressure zones using a separate riser, a fire pump and break tank arrangement, or pressure-regulating devices listed for the higher inlet pressure.
−
## Hose Connection Pressure Limits {toc}
…138 unchanged lines
- "Dedicated fire water storage tank and pump"
- "Combined public main and storage tank with pump"
−default: "Public water main with fire pump boost"
+default: "Public main with fire pump boost"
```
…12 unchanged lines
min: 20
max: 150
− setpoints: [40, 50, 60, 70, 80, 90, 100, 120, 150]
+ setpoints: [20, 40, 50, 60, 70, 80, 90, 100, 120, 150]
default: 70
```
…7 unchanged lines
min: 10
max: 130
− setpoints: [20, 30, 40, 50, 60, 70, 80, 100, 130]
+ setpoints: [10, 20, 30, 40, 50, 60, 70, 80, 100, 130]
default: 50
```
…291 unchanged lines
+### A pressure-regulating device shall be installed on every hose connection where the static pressure at the connection exceeds 175 psi (for 2-1/2 in. outlets) or 100 psi (for 1-1/2 in. outlets), or where the residual pressure at design flow would exceed those limits, in accordance with NFPA 14.
+
```datasheet
label: Pressure Regulation Required
…8 unchanged lines
```
−```datasheet
−label: PRV Outlet Pressure Set Point
−type: range
−unit: psi
−drawing_ref: true
−options:
− min: 75
− max: 175
− setpoints: [75, 100, 125, 150, 175]
−default: 125
−```
−### A pressure-regulating device shall be installed on every hose connection where the static pressure at the connection exceeds 175 psi (for 2-1/2 in. outlets) or 100 psi (for 1-1/2 in. outlets), or where the residual pressure at design flow would exceed those limits, in accordance with NFPA 14.
−
### A pressure-restricting device (PRD) is a fixed orifice or factory-set restriction at the hose valve outlet that limits the maximum flow and pressure, is field-settable to the design pressure during commissioning, does not actively regulate pressure as flow changes, is permitted where the static pressure does not exceed certain NFPA 14 limits, and is less expensive than a PRV. {note}
…8 unchanged lines
### The PRV selection schedule shall identify, for each outlet, the inlet static pressure, the inlet residual pressure at design flow, the required outlet set point, and the listed PRV model number with its applicable inlet pressure range.
+```datasheet
+label: PRV Outlet Pressure Set Point
+type: range
+unit: psi
+drawing_ref: true
+options:
+ min: 75
+ max: 175
+ setpoints: [75, 100, 125, 150, 175]
+default: 125
+```
+
### Each PRV or PRD shall be commissioned individually during the field acceptance test by measuring the actual inlet and outlet pressure at the design flow.
…93 unchanged lines
min: 250
max: 2500
− setpoints: [500, 750, 1000, 1250, 1500, 2000, 2500]
+ setpoints: [250, 500, 750, 1000, 1250, 1500, 2000, 2500]
default: 1000
```
…429 unchanged lines
## The Owner shall be advised that the spare parts inventory shall be replenished as items are consumed during NFPA 25 testing and maintenance over the life of the installation, and that PRV / PRD replacement diaphragms have a finite shelf life and shall be rotated periodically to ensure a usable spare is always available.