How to choose the right fire safety calculator
Start with the question you need answered. Most Texas building owners begin with extinguishers. Engineers and facility managers tend to move on to sprinklers and hazardous atmospheres.
- Use the fire extinguisher calculator to count units for a floor area.
- Use the sprinkler spacing calculator to lay out heads in a room.
- Use the hydraulic calculator to compare demand with your water supply.
- Use the pipe friction calculator to check pressure loss in one pipe run.
- Use the oxygen displacement calculator before you store or release inert gas indoors.
- Use the combustible dust reference to screen dust hazards under NFPA 660.
- Use the LEL and UEL lookup to find flammable limits for a gas or vapor.
- Use the gas mixture calculator when two or more fuels share the same space.
What these tools do and do not do
Each calculator turns a published rule into a number you can check by hand. Every page shows the formula and the table behind it. That makes the results easy to question, which is the point.
The tools do not replace a design. Texas requires licensed contractors for sprinkler and extinguisher work, and the State Fire Marshal's Office runs that licensing program. Your local fire marshal has the final say on code edition and field decisions.
Where the numbers come from
We pull limits from NFPA 10 for portable extinguishers, NFPA 13 for sprinklers, and NFPA 660 for combustible dust. Gas limits come from public safety references such as the NIOSH Pocket Guide to Chemical Hazards. Pipe friction uses the Hazen-Williams equation, the same method NFPA 13 uses for sprinkler hydraulics.
Codes change on a three-year cycle. A city may still enforce an older edition. Ask before you rely on any single table.
Frequently asked questions
Are these fire safety calculators free?
Yes. Every tool on this page is free. You do not need an account, and nothing you type leaves your browser.
Can I use these tools instead of a fire protection engineer?
No. The tools give planning numbers. A licensed Texas contractor or engineer must design and approve sprinkler, alarm, and suppression systems.
Which standards do the tools follow?
The extinguisher, sprinkler, and dust tools follow NFPA 10, NFPA 13, and NFPA 660. The gas tools use published flammable limits from sources such as the NIOSH Pocket Guide.
Who decides what is required at my building?
Your local authority having jurisdiction decides. That is usually the city or county fire marshal. Ask them which code edition applies before you buy or install anything.
Need a local supplier?
Once you have your numbers, browse the Texas supplier directory, check fire extinguisher services, or read our fire safety guides. You can also ask us for help finding a supplier in your city.