Beginning in 2000, minimum light output requirements were established for products evaluated per UL 924, Standard for Emergency Lighting and Power Equipment. At that time, incandescent luminaires with lamps of 5.4 W or greater and fluorescent battery packs whose input power was 4.5 W or greater were deemed to provide the minimum 1 foot-candle (fc) illumination level on the ground as required by the Life Safety Code (NFPA 101).
In 2011, UL established a separate product category (FTBV) for field-installable emergency LED drivers. Compared to the relatively standardized efficacy and photometric distribution of incandescent and fluorescent lamps, the performance of LED arrays was widely variable and changing rapidly. To establish compliance with the lumen output requirements of UL 924, UL’s certification program for these emergency LED drivers required evaluation with specifically identified LED luminaires. To highlight this limitation for meeting code compliance, UL turned to its Classification Mark which is designed to include such additional information.
Today, LED arrays, related supporting electronics, and the regulatory industry have evolved to establish a type of standardization that allows for much broader emergency LED driver–luminaire compatibility assessments. Output sensing circuitry that automatically adjusts to the forward voltage needs of the LED array, in combination with wider availability of 3rd party validated efficacy data, allows newer emergency LED drivers to be found suitable for many applications without the need for individual driver–luminaire lumen output testing. While these suitability assessments are not particularly simple, the task is considered to be within reasonable skillset expectations for the professional installer community.
The suitability assessment guidance is a required element of the emergency LED driver installation instructions. The necessary information is far beyond what can fit within the limited space on the UL Classification Mark so the advantage of using this Certification Mark is greatly diminished. As a result, UL is shifting its FTBV program to allow for the use of the more familiar UL Listing Mark. Listed emergency LED drivers still require a ‘suitability assessment needed’ statement on the driver, directing the installer to either the product installation instructions or the manufacturer’s website for the needed information. The enhanced UL Certification Mark option remains available for FTBV products.
This change will not require any changes to product design or operation as it involves only a change in the type of UL Certification Mark applied to the emergency LED driver. For information regarding product markings and UL Certification references in accompanying required documents (installation instructions, website information, etc.), please see below:
- If the enhanced UL Certification Mark is currently being applied, no change is needed.
- If the UL Classification Mark is currently being applied, the markings and references should be updated to the UL Listing Mark by the end of 2017. This transition period is intended to allow existing label inventories to be used and for marketing materials and programs to be adjusted. During the transition, any UL Marks (Classification, Listing or Certification) may be used.
UL expects this change will help the market by:
- Improving perceptions of ‘safety’ equity between comparable emergency fluorescent ballasts (which have always been eligible to use the UL Listing Mark) and emergency LED drivers.
- Reducing uncertainty amongst those unfamiliar with the less frequently seen UL Classification Mark.
- Eliminating confusion as to whether a UL Classified product is a “listed” product in the context of the NEC due to all UL Listed or Classified products being “listed” per the definition of this term in the NEC.
- Eliminating perceived inequities between UL Classified or Certified equipment and comparable equipment listed by other agencies that do not have different mark programs.
UL created a set of Frequently Asked Questions (FAQs) that provides additional details on the program and the transition. The FAQs can be viewed below.