Determining the right number of fire extinguishers for your building or facility is an important fire safety measure. Having too few extinguishers can leave you vulnerable in the event of a fire, while having more than you need leads to unnecessary costs. Calculating your fire extinguisher requirements depends on several factors like building size, occupancy hazard, and applicable fire codes.
How many fire extinguishers are needed by law?
Most local jurisdictions follow NFPA 10 standards for portable fire extinguisher requirements. These rules provide a baseline for the minimum number of extinguishers needed based on things like:
- Building size and floorspace
- Hazard classification and combustible materials present
- Maximum travel distance to an extinguisher
NFPA 10 dictates that the maximum travel distance to a fire extinguisher should be no more than 75 feet. That means an extinguisher must be located within 75 feet of all portions of the building floor. For higher hazard commercial facilities, the required travel distance is reduced to 50 feet.
What are the standard spacing and quantity rules?
In addition to travel distance, NFPA 10 provides general guidance for spacing and quantity:
- Extinguishers must be located in conspicuous locations where they will be readily accessible and immediately available for use
- Distribution should ensure uniform coverage within the spacing limitations
- At least one extinguisher must be provided for each floor level
- Additional extinguishers may be needed near hazardous areas like mechanical or electrical rooms
Some jurisdictions may have additional rules about things like minimum extinguisher ratings and where they can be located. Always check local fire codes for any specific requirements in your area.
How do I calculate the needed number of fire extinguishers?
Figuring out the right amount of fire extinguishers involves taking into account the size and layout of your property along with any hazard considerations. Here is a step-by-step guide:
1. Determine the floor space square footage
First, calculate the total floor space square footage for your building. Include all levels and divide up any spaces with partial floors. This gives you the baseline area you need coverage for.
2. Divide floorspace by maximum travel distance
Next, divide your total floor space by the maximum travel distance to an extinguisher per local codes (usually 75 feet). This gives you the minimum number of extinguishers needed to comply with travel distance rules.
For example, a 10,000 square foot facility would need 10,000/75 = 133 extinguishers to have one every 75 feet.
3. Adjust for hazard areas
Now review your floor plan and identify any spaces that may require extra extinguishers due to posing higher fire risks. This may include:
- Electrical and mechanical rooms
- Kitchens and cooking areas
- Laboratories, workshops, or manufacturing areas
- Warehouses or storage rooms, especially for hazardous materials
- Parking garages, special events venues, or other areas with temporary hazards
Add additional extinguishers as needed in these areas, keeping travel distances in mind.
4. Confirm uniform coverage
Check your floor plan with tentative extinguisher placements marked. Make sure coverage looks even throughout, with spacing that meets travel distance limits. Adjust placements if there are any gaps or sections that look underserved.
Spacing should also factor in physical barriers. For example, an extinguisher located across a locked door would not have accessible coverage.
5. Include minimum required extinguishers
Remember to place at least one extinguisher per floor level. And check that any mandatory extinguishers for specific hazards or equipment are included.
6. Consider supplemental coverage
For facilities with heightened fire risks, added protection can be prudent. Consider supplementing with additional extinguishers in busy or dangerous areas even if not required. It is also smart to keep extra extinguishers in supply for replacements or temporary needs.
How do I determine my building’s hazard classification?
NFPA assigns hazard classifications that help determine what fire protection measures are required. The three main classifications are:
- Light (Low) Hazard – Areas like offices, classrooms, museums, retail stores, etc. with minimal flammable materials.
- Ordinary (Moderate) Hazard – Facilities like restaurants, auto shops, parking garages and warehouses with moderate combustibles.
- Extra (High) Hazard – Places with concentrated flammables like factories, oil refineries, chemical plants and grain elevators.
The hazard level impacts things like the types of required extinguishers and their maximum travel distances. Facilities are evaluated based on:
- Types and amounts of flammable and combustible materials regularly present
- Likelihood of fires occurring and spreading rapidly
- Possibility of extreme fire hazards arising like explosive vapors or combustible dust
If your property contains minimal fuels and low fire risks overall, it likely qualifies as light hazard. Places with more combustibles and ignitable conditions would be ordinary or extra hazard. When in doubt, consult your local fire marshal.
How do I create a fire extinguisher placement plan?
A fire extinguisher placement plan maps out where your extinguishers should be located to meet legal and safety requirements. Creating a plan involves:
1. Draw a floor plan
Sketch out floor plans for each level of your building. Include all rooms, hallways, exits, stairs, elevators and major permanent features. Mark dimensions if known.
2. Indicate hazards
Note any fire hazards like chemical storage areas, fuel tanks, kitchens, workshops, etc. This highlights areas that may need extra extinguishers.
3. Add planned extinguisher locations
Based on your calculations and spacing guidelines, mark tentative extinguisher placement spots on the floor plan. Remember to include minimum per floor requirements.
4. Check coverage
Review the locations against your floor space and travel distance needs. Adjust spots as needed to provide complete uniform coverage.
5. Finalize optimal positions
Determine the best final extinguisher positions considering traffic paths, accessibility, hazards and convenient visibility. Mark these clearly on the floor plans.
6. Indicate key details
Note the planned extinguisher type for each location based on the hazard rating. Also mark special cases like taller cabinet units or supplemental outdoor extinguishers.
What types of fire extinguishers are needed for different risks?
Choosing the right extinguisher types for your risks can optimize fire protection. Here are common extinguisher classes and suitable uses:
| Extinguisher Type | Intended Uses |
|---|---|
| Class A | Common combustibles like wood, paper, cloth and many plastics |
| Class B | Flammable liquids like gasoline, oil and grease |
| Class C | Electrical equipment fires |
| Class D | Combustible metals like magnesium and sodium |
| Class K | Cooking oils and fats like in commercial kitchens |
| Class ABC | Most common combustibles, suitable for general purpose use |
| Class DRY | Dry chemical agents, useful for multi-purpose protection |
Refer to hazard safety data sheets and local fire codes to determine the right types of extinguishers for your unique risks.
How do I inspect and maintain fire extinguishers?
Regular inspection and maintenance helps ensure extinguishers remain in good working order when needed. Follow these best practices:
Monthly Inspections
- Check extinguisher is in designated location, with easy access and no obstructions
- Verify tamper seal is intact and pressure gauge (if present) indicates full charge
- Check for damage, corrosion, leaks or clogs – replace if found
- Weigh cartridge extinguishers to confirm full weight
Annual Maintenance
- Conduct thorough check of all components
- Test extinguisher discharge
- Inspect hose and nozzles for cracks or blockages
- Check cartridge weights and recharge if 5-10% low
- Update tags with service date and initials
Six Year Maintenance
- Perform hydrostatic pressure testing on tanks
- Conduct internal examination of components
- Recharge extinguisher and replace parts as needed
Always follow manufacturer instructions for model-specific maintenance procedures. Keep detailed records of all inspections and service work performed.
Conclusion
Determining fire extinguisher requirements involves calculating your floorspace coverage needs based on travel distances, adjusting for hazard areas, creating a placement plan, and selecting suitable extinguisher types. Maintaining extinguishers properly through routine inspections and service ensures they function as critical first aid fire protection. Referencing fire codes, seeking input from safety experts, and staying vigilant can help identify risks and customize an effective fire extinguisher plan.
