UL 924 is the most important standard for anyone installing exit signs and emergency lights. It ensures your equipment performs reliably when the power goes out. This guide explains what UL 924 is, why it matters, and how to ensure compliance in your building. You’ll also see how UL 924 interacts with NEC/IFC and AHJ inspections.
Related compliance planning: For local adoption and California energy-code context, use the U.S. fire codes hub, state fire marshal directory, and Title 24 compliance guide.
📘 What Is UL 924?
UL 924 is the standard for Emergency Lighting and Power Equipment. Created by Underwriters Laboratories, it certifies exit signs, emergency lights, and battery backup systems for safety, performance, and reliability during power outages.
UL 924 is required by NFPA 101, IBC, IFC, OSHA, and most local fire codes across the U.S.
🚨 Why UL 924 Matters
- Verifies exit signs and emergency lights meet critical brightness and duration requirements
- Ensures reliable backup power and fast startup during an outage
- Supports life safety systems during fire marshal inspections
- Protects liability, reduces insurance risk, and supports AHJ approvals
If it’s not UL 924 listed, it likely isn’t code compliant.
📏 Key UL 924 Requirements
- Must provide 90 minutes of illumination during power failure
- Signs must emit a minimum of 1 footcandle of light at floor level
- Lighting must turn on within 10 seconds of power loss
- Battery systems must recharge within 24 hours
- All testing must be documented and verifiable
Local codes often set egress illumination (for example, one footcandle initial under NFPA 101); UL 924 verifies equipment can achieve that performance safely and consistently.
💡 Products That Require UL 924 Listing
- LED and photoluminescent exit signs (with internal backup)
- Combination exit sign / emergency light units
- Recessed and wet-location emergency lights
- Battery packs, central inverter systems, and self-testing units
Even decorative or architectural signs must meet the same safety and performance benchmarks.
🧪 UL 924 Testing & Certification
To be UL 924 listed, products must undergo:
- Brightness and visibility testing (in dark, smoky, and real-use conditions)
- Battery discharge and recovery testing
- Durability under vibration, moisture, and corrosion
- Electrical isolation and shock resistance validation
All certified units carry a UL label or marking for easy inspector reference.
❓ UL 924 FAQ
-
Is UL 924 required by law?
Yes—most U.S. codes require listed equipment, and UL 924 is the nationally recognized standard. -
Can I use non-UL signs?
Only if your AHJ has specifically approved them—but this is rare and not recommended. -
What if I install older fixtures?
They may be grandfathered in, but any upgrades or remodels require UL 924 units.
📚 Helpful Resources
- UL Standards & Certification Info
- NFPA Life Safety Code (101)
- Shop UL 924 Exit Signs & Emergency Lights
🧠 Final Thoughts
If you’re working with exit signs or emergency lights, UL 924 is your compliance anchor. Look for the UL mark, follow manufacturer testing protocols, and document your inspections—it’s the safest (and smartest) path to code compliance and occupant safety.