What are the key Changes in Chapter 9 Fire Protection Systems California Building Code 2025?

Chapter 9 contains substantial additions and structural changes, especially around sprinklers, fire alarms, mass notification, lithium-ion battery hazards, hybrid extinguishing systems, standpipes, and supervision requirements.

Major categories of changes include:

1. Lithium-Ion Batteries (biggest theme in Chapter 9)

New sprinkler triggers, fire test requirements, and alarm system requirements added for:

• Battery storage (S-1, M)
• Labs testing batteries (Group B)
• Manufacturing (Group F-1)
• Battery-powered vehicles (S-1 repair garages)
• ESS rooms

2. Sprinkler System Design & Supervision Changes

• NFPA 13R permitted in more R-2 buildings
• Removal of specific exemptions
• New sprinkler test-based design for Li-ion hazards
• New inspection requirements (not just test/maintenance)

3. Fire Alarm System Changes

• Major updates for Group A, Group B labs, lithium battery facilities
• New mass-notification risk analysis for large Group E buildings
• Relocation of amusement area alarm requirements

4. Standpipes

• New exceptions (e.g., townhouse exemption)
• New requirements for fixed-guideway transit systems
• Updated hose connection locations

5. FDC Signage

New prescriptive signage requirements added to CBC for the first time.

This is a highly consequential chapter for:

• MEP firms
• Fire protection engineers
• Battery storage designers
• Lab facilities
• Parking structure and EV garage designers
• Schools, hospitals, commercial mixed-use projects

‍

General Fire Protection System Administration

‍

Automatic Sprinkler Requirements (903)

‍

Special Hazards, Extinguishing Systems (904)

‍

Standpipes (905)

‍

Fire Extinguishers (906)

‍

Fire Alarm & Detection Systems (907)

‍

Smoke Control (909)

‍

Fire Department Connections (912)

‍

Carbon Monoxide Detection (915)

‍

Mass Notification (917)

‍

Expert Commentary — Why Chapter 9 Is One of the Biggest in the 2025 CBC

1. Lithium-Ion Batteries: The New “Sprinkler Trigger” Frontier

This is one of the largest CBC shifts in the last decade. The code now assumes:

• Li-ion = inherently high hazard
• Must be specially sprinkled
• Must be specially alarmed
• Must be specially designed based on tests

This affects:

• EV parking
• Battery retail
• ESS installations
• Labs
• Industrial manufacturing
• Postal centers and warehouses

2. NFPA 13R Expansion for R-2 < 45 ft Roof Height

This is extremely important for:

• Urban infill
• Podium mid-rise apartments
• Mixed-use residential

This change reduces construction cost significantly.

3. Mass Notification for Group E

School districts will now face:

• Mandatory risk assessments
• Potential installation of expensive systems

4. Revisions to Standpipe Requirements

Transit systems and EV garages will see changed standpipe requirements.

5. Hybrid Fire Extinguishing Systems

Opens the door for:

• Water-mist systems
• Mixed-media suppression for labs, battery rooms, server rooms

‍

FAQs

1. What are the biggest overall changes in CBC 2025 Chapter 9?

CBC 2025 significantly expands fire protection rules in five areas:

• Lithium-ion battery hazards
  
• Automatic sprinkler triggers and design
  
• Fire alarm and mass-notification systems
  
• Standpipes and hose connection locations
  
• Hybrid extinguishing systems and FDC signage
  

This is one of the largest Chapter 9 rewrites in over a decade.

2. Why is lithium-ion battery protection such a dominant theme?

Because California is seeing rapid growth in EVs, energy storage, robotics, and battery-heavy retail. The code now treats Li-ion hazards as inherently high-risk, adding new triggers for sprinklers, fire alarms, detection systems, and test-based sprinkler design for battery fires.

3. What new sprinkler requirements affect battery-related spaces?

CBC 2025 adds sprinkler triggers for:

• Li-ion labs (B occupancy)
  
• Battery manufacturing (F-1)
  
• Battery retail/storage (M occupancy)
  
• EV repair areas (>500 sq ft)
  
• S-1 spaces storing battery-powered vehicles
  

Nearly every space handling Li-ion products must now be sprinkled.

4. How does the new fire test–based sprinkler design requirement work?

Section 903.3.1.1.3 now requires sprinkler design based on actual fire test data for lithium-ion battery hazards. This eliminates generic design curves and forces custom engineering or tested design methods.

5. Did CBC 2025 make it easier to use NFPA 13R?

Yes. R-2 buildings may use NFPA 13R if the roof is <45 ft above fire department access. This is a major cost savings for mid-rise multifamily and mixed-use projects.

6. What fire alarm updates should designers pay attention to?

Key changes include:

• New alarm requirements for battery labs, storage, and manufacturing
  
• Expanded detection rules (air-sampling, radiant detection allowed)
  
• A new mass-notification risk analysis for large Group E buildings
  
• Relocation of amusement area requirements to Section 411
  

These changes impact schools, labs, EV facilities, and assembly venues.

7. How do the mass-notification changes affect schools?

Group E buildings with >500 occupants must complete a risk analysis. If risks are present, the building must install an NFPA-72 compliant mass communication system. This will add cost and complexity for many new K–12 and higher ed projects.

8. What changed for standpipe requirements?

Major updates include:

• Townhouses are now exempt
  
• Fixed-guideway transit systems newly covered
  
• Hose connection locations clarified (stairways, balconies, auditorium rear)
  

These affect multifamily, transit agencies, and assembly occupancies.

9. What’s new about FDC signage?

CBC 2025 introduces the state’s first prescriptive FDC labeling requirements (Sections 912.5.1–912.5.3). Designers must now include specific, standardized signage—no more jurisdiction-by-jurisdiction guesswork.

10. What are hybrid fire extinguishing systems, and why are they now included?

Hybrid systems (referencing NFPA 770) combine water mist and gas to suppress hard-to-control fires. CBC now includes them because they’re increasingly used for:

• Battery rooms
  
• Labs
  
• Robotics
  
• Data rooms
  ‍

This opens new pathways for non-traditional suppression systems.

11. Did the CBC change inspection and supervision requirements for sprinklers?

Yes. Changes include:

• Added requirement for inspection (not only testing/maintenance)
  
• Expanded supervision for limited-area sprinkler valves
  
• New audibility and visibility requirements for waterflow/supervisory alarms
  

These improve reliability and align CBC with NFPA 25.

12. How do the changes impact EV repair garages and parking structures?

CBC now requires:

• Sprinklers for EV repair areas >500 sq ft
  
• Sprinklers for S-1 spaces storing battery-powered vehicles
  

These changes will affect dealerships, municipal fleets, logistics companies, and large parking structures.

13. Who is most impacted by the 2025 fire protection changes?

The chapter heavily affects:

• MEP and fire protection engineers
  
• EV and battery facility designers
  
• Lab/R&D buildings
  
• Parking structures and mixed-use EV-enabled projects
  
• Schools and higher education
  
• Transit agencies
  
• Multifamily developers
  
  

14. Why did CBC remove the integrated testing section (901.6.2)?

Because the previous integrated testing rules were overly burdensome and unclear for typical facilities. Removing the section reduces unnecessary multi-system testing requirements unless specifically mandated elsewhere.

15. Will AHJs interpret these changes uniformly?

Unlikely. Lithium-ion, mass-notification, and hybrid systems are new territory for many jurisdictions. Expect:

• additional questions
  
• local amendments
  
• variable enforcement
  ‍

This is a prime area where Melt Code can help reduce ambiguity.

References

1. ‍2022 California Building Code, Title 24, Part 2 (Volumes 1 & 2) with July 2024 Supplement updated

2. 2025 California Building Code Volumes 1 and 2, Title 24, Part 2