Fire Extinguisher Spacing Calculator

How It Works

1. Select Hazard Row

   Choose the closest local planning row for the area. Do not treat this as the final occupancy, commodity, process, or code classification.

2. Enter Area Inputs

   Enter length, width, floors, exits or stairwells per floor, and any flammable-liquid or commercial-kitchen flags.

3. Review Count Drivers

   Compare the local coverage row, user-entered exit count, and open-floor travel grid count. The app uses the largest driver for the Class A planning count.

4. Walk Actual Travel Paths

   Check aisles, doors, walls, racks, machinery, storage, and locked areas. Travel distance is the path a person can actually walk.

5. Confirm Sources

   Verify NFPA 10, OSHA, extinguisher listings, maintenance requirements, employee policy, and AHJ direction before installation or inspection use.

Built For

• Facility managers roughing out extinguisher counts before a qualified fire-protection review
• Safety officers checking whether a plant rearrangement may have changed walking paths and access
• Maintenance planners preparing a list of areas to inspect with a fire extinguisher vendor
• Restaurant owners flagging Class K review needs before talking with the hood and extinguisher service provider
• Property managers gathering dimensions and hazard notes before an AHJ or insurer walkthrough
• Contractors separating permanent building placement questions from temporary jobsite fire protection questions

Features & Capabilities

Count Driver Comparison

Shows the local coverage row count, user-entered exit count, and open-floor travel grid count before selecting the largest value.

Open-Floor Travel Screen

Uses a straight-line rectangular screen for rough planning while warning that actual walking paths must be field checked.

Class B and Class K Flags

Adds planning screens when flammable-liquid or commercial-kitchen hazards are present, with warnings that each hazard needs site-specific review.

Source Boundaries

Labels OSHA, NFPA, maintenance, listing, training, and AHJ limits so the output is not mistaken for approval.

Malformed State Guarding

Shared links and autosaved values are normalized before calculation so bad state does not produce nonfinite output.

PDF Export

Exports the planning screen, assumptions, source warnings, and source pointers for review notes.

Assumptions

• The user-selected hazard row is a planning row, not a final fire-code classification
• Class A count is the maximum of local coverage row count, user-entered exit count, and open-floor travel grid count
• Open-floor grid spacing uses travel distance times square root of 2 for a straight-line square-cell screen
• Class B flag applies an open-floor travel screen to the entered rectangle, not the actual flammable-liquid hazard geometry
• Class K flag assumes one commercial cooking hazard per floor because appliance and hood layout are unknown
• Costs are placeholders and exclude brackets, cabinets, signs, service, inspection, permits, tax, delivery, and labor

Limitations

• Does not account for shelving, machinery, partition walls, locked doors, mezzanines, exterior areas, or blocked access
• Does not select extinguisher agent, rating, listing, cabinet, bracket, signage, mounting height, or maintenance interval
• Does not determine employer evacuation policy, employee-use training, inspection records, or hydrostatic test status
• Class D, oxidizer, clean-agent, CO2, laboratory, server-room, vehicle, marine, and other special hazards need separate source review
• Construction-phase temporary requirements under OSHA 1926.150 may differ from permanent building placement
• Local fire code amendments, insurance requirements, and AHJ direction can override a simple planning screen

References

1. OSHA 29 CFR 1910.157 - Portable Fire Extinguishers source pointer
2. NFPA 10 - Standard for Portable Fire Extinguishers source pointer
3. OSHA 29 CFR 1926.150 - Fire Protection in Construction source pointer
4. Current adopted fire code, local amendments, extinguisher listings, manufacturer instructions, and AHJ direction

Frequently Asked Questions