UL 924 Explained: What the Emergency Lighting Listing Covers

UL 924 is the standard for emergency lighting and power equipment such as exit signs, emergency luminaires and unit equipment. The most useful thing to know about it is that it covers two kinds of equipment, emergency and auxiliary, and auxiliary equipment has not been investigated for the performance requirements of NEC Article 700 or 701, NFPA 101 or the International Building Code. This guide explains what UL 924 covers and what to look for on a spec sheet. Where emergency lighting is required in a building is covered in our guide to emergency and exit lighting code requirements.

What UL 924 is

UL 924 is the Standard for Emergency Lighting and Power Equipment, published by UL Standards & Engagement. The current version is Edition 10, published May 9, 2016 and most recently revised February 12, 2025, the same date it was approved as an American National Standard.

Its scope, as UL Standards & Engagement publishes it, covers "emergency lighting and power equipment for use in unclassified locations and intended for connection to branch circuits of 600 volts or less." It also covers "photoluminescent and self-luminous exit signs that do not connect to a branch circuit." The equipment is intended "to automatically supply illumination or power or both to critical areas and equipment in the event of failure of the normal supply," in accordance with NEC Article 700 or 701, NFPA 101, NFPA 1, the International Building Code and the International Fire Code.

Equipment for classified (hazardous) locations must also meet additional or alternative requirements outside the scope of UL 924.

What equipment it covers

UL Standards & Engagement gives these examples of emergency equipment in scope:

• Exit signs
• Emergency luminaires
• Unit equipment
• Central station battery banks
• Inverters
• Automatic battery charging and control equipment
• Emergency lighting control devices, such as automatic load control relays and derangement signals

Emergency vs auxiliary: the distinction that matters

UL 924 also applies to what it calls auxiliary lighting and power equipment. In the standard's own scope: "Auxiliary equipment has not been investigated to determine compliance with the performance requirements of Article 700 or 701 of the National Electrical Code, NFPA 70, the Life Safety Code, NFPA 101, or the International Building Code. Such equipment includes luminaires with an integral battery backup power supply, illuminated directional signs, battery assemblies, and related devices."

So "UL 924" on a spec sheet is not the whole answer. If the product is going into a code-required emergency system, confirm with the manufacturer that it is intended for that emergency use, not auxiliary use. A luminaire with integral battery backup can fall on either side, which is exactly why the check matters.

UL 924 and safety listings

For some equipment, UL 924 is not the only standard involved. According to UL Standards & Engagement, the basic protection against fire, electric shock and injury for some equipment in its scope is covered by other standards, such as UL 1598 for luminaires and UL 1008 for branch circuit emergency lighting transfer switches. In those cases, "the primary role of UL 924 ... is to validate compliance with emergency system functionality and performance expectations."

UL Solutions, which tests and certifies to the standard, makes the same point from the other direction: UL 924 "has extra investigatory steps beyond general lighting certifications." A general UL mark on a fixture is not the same thing as UL 924 certification of its emergency function.

Emergency lighting and lighting controls

UL Solutions describes emergency lighting as including "luminaires with integral batteries or bypassable dimming controls that provide illumination when the normal power supply is disrupted," and notes that "UL 924 also includes an evaluation of controls called the Emergency Lighting Control Functionality (ELCF) test." The standard's scope names emergency lighting control devices, such as automatic load control relays, among the equipment it covers.

If emergency fixtures will sit on the same dimming or occupancy controls as the normal lighting, plan the control path with the fixture and control manufacturers' documentation, and confirm how each device in that path is listed.

How to check a listing

• Read the spec sheet. Look for UL 924 named for the emergency function, and confirm with the manufacturer whether the product is intended for emergency or auxiliary use. Our guide to reading a lighting spec sheet shows where listings appear.
• Use UL Solutions' database. UL Solutions points to its Product iQ database "to learn more about different certified emergency lighting products and categories."
• Match the paperwork. Tie the spec sheet, the submittal and the order to the same part number.

Shop UL 924 equipment at Rock

Rock Lighting & Electric carries UL 924 emergency lighting equipment and exit signs. Create a contractor account, request a quote, or send us your fixture schedule and we will help you find emergency options for the fixtures on your job.

Frequently asked questions

What is UL 924? UL 924 is the Standard for Emergency Lighting and Power Equipment, published by UL Standards & Engagement. It covers emergency lighting and power equipment for unclassified locations on branch circuits of 600 volts or less, plus photoluminescent and self-luminous exit signs that do not connect to a branch circuit. The equipment is intended to supply illumination or power automatically when the normal supply fails. The current version is Edition 10, most recently revised February 12, 2025.

What products are covered by UL 924? UL Standards & Engagement gives examples including exit signs, emergency luminaires, unit equipment, central station battery banks, inverters, automatic battery charging and control equipment, and emergency lighting control devices such as automatic load control relays and derangement signals.

What is auxiliary equipment under UL 924? UL 924 also applies to auxiliary lighting and power equipment, which has not been investigated for compliance with the performance requirements of NEC Article 700 or 701, NFPA 101 or the International Building Code. The standard's examples include luminaires with an integral battery backup power supply, illuminated directional signs and battery assemblies.

Is a UL listed fixture the same as UL 924 listed? No. UL Solutions describes UL 924 as having extra investigatory steps beyond general lighting certifications, and UL Standards & Engagement says its main role for equipment such as luminaires is to validate emergency functionality and performance. Check that the emergency function is covered by UL 924, and confirm with the manufacturer that the product is intended for emergency, not auxiliary, use.

Does UL 924 cover emergency lighting controls? Yes. Its scope includes emergency lighting control devices such as automatic load control relays, and UL Solutions notes that UL 924 includes an Emergency Lighting Control Functionality (ELCF) test.

How do I check if a product is UL 924 listed? Check the spec sheet for UL 924 named for the emergency function, confirm with the manufacturer whether the product is intended for emergency or auxiliary use, then use UL Solutions' Product iQ database, which it points to for certified emergency lighting products and categories.

---