A win for industry-led standards as ABYC C-5 replaces decades-old UL 1104

ANNAPOLIS, Md. (June 24, 2025) – The American Boat & Yacht Council (ABYC) announced that the U.S. Coast Guard (USCG) has officially accepted ABYC C-5, Construction and Testing of Electric Navigation Lights, as an equivalent to UL 1104, according to Policy Letter 01-25.This acceptance gives manufacturers and boat builders a modern way to meet compliance, especially for vessels over 65 feet (19.8 meters) in length.

“ABYC C-5 is a technology-forward standard that reflects how navigation lights are built today,” said Craig Scholten, ABYC vice president of standards and compliance. “This is what success looks like when industry and regulators work together.”

Vessels over 65 feet must use navigation lights that meet UL 1104 or another standard specified by the Commandant. The Coast Guard’s acceptance of ABYC C-5 fulfills this requirement with a current, relevant standard. 

The current edition of UL 1104 was produced in 1998. Since then, the technology used in navigation lights has dramatically changed. UL 1104 was not devised to address light-emitting diode (LED) navigation lights, and various tests it requires are not applicable to LED technology. Additionally, LED lights present different failure modes that are not addressed in UL 1104 testing.

ABYC C-5 addresses this gap with updated testing requirements and international alignment. It applies to vessels of all sizes and includes standards for both incandescent and LED navigation lights—covering visibility, color, service life, electromagnetic compatibility, materials, and labeling. The C-5 standard aligns with ISO 19009 Electric navigation lights — Performance of LED lights.

Where Titles 33 and 46 of the Code of Federal Regulations (CFR) require navigation lights to be certified, a USCG accepted independent laboratory may be authorized under approval series 111.075 to certify navigation lights as meeting ABYC C-5.

For more information or to access the standard, visit www.abycinc.org or contact techs@abycinc.org.

Summary: What Manufacturers Should Know

  • UL 1104 is outdated and no longer maintained. It does not reflect LED technology or modern performance needs.
  • ABYC C-5 is now officially accepted by the U.S. Coast Guard for compliance with navigation light regulations.
  • ABYC C-5 applies to all vessel sizes, not just those under 65 feet
  • Covers both incandescent and LED lights, including requirements for:
    • Luminous Intensity and Range of Visibility
    • Chromaticity Area Requirements
    • Degradation Caused by Service Life Conditions
    • Materials and Construction
    • Testing Requirements including Electromagnetic Compatibility
    • Marking
    • Owner’s Manual and Collateral Literature
  • Aligns with ISO 19009 for international consistency.
  • Most new lights already meet C-5, offering a wide range of compliant options.
  • Lights can be certified through Coast Guard–accepted labs listed in CGMIX.

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Since 1954, the nonprofit American Boat & Yacht Council has developed safety standards for boat design, construction, equipage, repair and maintenance. As the essential global source of marine industry technical information, ABYC supports its members with safety standards, credentialing, education, training and technical tools to help make boating safer.