Sprinkler Hydraulic NFPA 13

About Sprinkler Hydraulic NFPA 13

Sprinkler hydraulic calculations per NFPA 13: design density, remote area, sprinkler flow and pressure, friction loss and total system demand.

WHAT IT CALCULATES
- Design density and area from the density/area curves, interpolated between the listed points
- Sprinkler discharge from the K-factor: flow equals K times the square root of pressure
- Coverage per head: up to 225 sq ft light, 130 sq ft ordinary, 100 sq ft extra hazard
- Hazen-Williams friction loss with C-factors: 120 steel, 150 copper and CPVC, 100 cast iron
- Hose stream allowance added to the sprinkler demand
- Total demand in gpm at the pressure the supply has to deliver

CODE REFERENCES BUILT IN
- NFPA 13 Figure 11.2.3.1.1 - density and area curves
- NFPA 13 Table 8.5.2.1 - maximum coverage area per sprinkler

HOW IT WORKS
Enter hazard, remote area, K-factor, pipe material and length. You get density, flow per head, friction loss, hose allowance and the total demand.

CORE FEATURES
- Works 100 percent offline, no signal needed on site
- Calculation history you can reopen and reuse
- PDF export for submittals and field records
- Light and dark themes
- English and Spanish
- Material Design 3 interface

TYPICAL USES
- Checking a layout on site before the pipe goes up
- Verifying a contractor submittal during plan review
- Sizing during a bid walk without pulling the code book out of the truck
- Backing a field decision with a PDF you can attach to the job file
- Studying for NICET certification

WHAT THE PDF REPORT INCLUDES
- Every input you entered
- The calculated results with units
- Date and time of the calculation

OPTIONAL PRO UPGRADE - $2.99 ONE-TIME IN-APP PURCHASE
The following features require a separate one-time in-app purchase. They are not required to use the calculator:
- Unlimited saved calculation history
- PDF export of results
- Dark theme
- Ad-free experience

WHO IT IS FOR
- Fire protection engineers and system designers
- Sprinkler fitters and installers
- Fire inspectors and AHJ plan reviewers
- Contractors preparing bids and submittals
- NICET candidates and fire protection students

ACCURACY NOTE
Results are a design aid, not a stamped design. Verify against the edition of the standard adopted in your jurisdiction and confirm with the authority having jurisdiction.

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