NFPA in USA

Reference library

Fire protection reference tables

Structured lookup tables that support calculator setup and engineering checks.

C valuesK-factorsPipe dimensionsAWG resistanceHazard classes

Tables

8

Engineering lookup pages

Linked tools

30

Calculator library

Use

Setup

Inputs and screening checks

How reference tables support the calculators

Use these tables to select C values, K-factors, internal pipe diameters, equivalent fitting lengths, density and area baselines, AWG resistance, and hazard classes before running a calculator.

Tables

Reference tableLookup purposeUsed byOpen

Hazen-Williams C Values for Fire Sprinkler Pipe

Hazen-Williams C values pipe

Lookup common Hazen-Williams roughness coefficients for steel, copper, CPVC, cast iron, and dry-system sprinkler pipe materials.2 linked calculatorsOpen

Fire Sprinkler K-Factor Table

sprinkler K-factor table

Reference common sprinkler K-factor values used for quick flow and pressure checks in NFPA 13 style sprinkler calculations.2 linked calculatorsOpen

Sprinkler Pipe Internal Diameter Reference

pipe internal diameter schedule 10 40

Compare typical Schedule 10 and Schedule 40 internal pipe diameters used in sprinkler hydraulic and velocity calculations.2 linked calculatorsOpen

Equivalent Pipe Lengths for Common Fittings

equivalent pipe length fittings NFPA 13

Reference common equivalent length allowances for fittings when estimating sprinkler pipe friction loss and remote-area demand.2 linked calculatorsOpen

NFPA 13 Design Density and Area Reference

NFPA 13 density area curve

Lookup common density and design-area combinations for light, ordinary, and extra hazard sprinkler design screening.2 linked calculatorsOpen

AWG Wire Resistance Table for Fire Alarm Circuits

AWG wire resistance table

Lookup copper conductor resistance values for fire alarm NAC and SLC voltage drop calculations using common AWG sizes.2 linked calculatorsOpen

Occupancy Hazard Classification Reference

NFPA 13 occupancy hazard classification

Screen common occupancy examples against broad NFPA 13 hazard classes for early sprinkler design scoping and calculator setup.2 linked calculatorsOpen

US Code Adoption and AHJ Checkpoints

US fire code adoption AHJ checklist

Use this jurisdiction checklist before applying NFPA calculators on a United States project because adopted editions, local amendments, and AHJ direction can vary.3 linked calculatorsOpen