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5 Key Changes to FAA AC 70/7460 Obstruction Lighting Regulations

The FAA maintains three advisory circulars governing the use of aviation obstruction lights in the United States:


  • FAA AC 150/5345-43 details how manufacturers should build aircraft warning lights.
    The latest version, 43J, went into effect on September 11, 2020. Manufacturers must build the lights per the specifications found in 43J in order to be certified and listed in the addendum to AC 150/5345-53.


  • FAA AC 70/7460-1 outlines how structures should be lit, monitored and maintained.
    The latest version, 1M, went into effect on November 16, 2020. It alters federal lighting regulations for new and refined sites. Structures must be marked with lights that are certified and listed in the AC 150/5345-53 addendum.


  • FAA AC 150/5345-53 discusses the equipment certification program and lists compliant products in the addendum.
    AC 150/5345-53 outlines third-party testing requirements in order to ensure lights meet the specifications from AC 70/7460. Only lights passing rigorous third-party testing are certified and listed in the addendum to 150/5345. In addition, the FAA describes in-house compliance and quality control testing that manufacturers must perform before each product ships.


Sites filed under version 1L or older are not required to refile to 1M. Owners of these sites should assess potential liabilities to air safety when choosing whether to refile.

Changes to Federal Lighting Regulations


1. Infrared Obstruction Lights


Last year the FAA specified changes for red LED obstruction lights in order to increase visibility for pilots using night vision goggles with class B filters. For background information on this change, please read our article in AGL Magazine’s August 2020 issue.


Under FAA AC 150/5345-43J, manufacturers like Flash Technology are required to build lights in accordance with these new specifications.


Under FAA AC 70/7460-1M, tower owners are required to deploy red/infrared lights by purchasing equipment listed in the addendum to FAA AC 150/5345-53D. In addition, since infrared is invisible to the naked eye, use a monitoring device that can differentiate between red, infrared and white LED strings.


2. Obstruction Height Definition


The FAA changed the prior definition of an obstruction. Structures lower than 499 feet AGL may be considered obstructions and would need to be marked accordingly.


3. Marking and Lighting Temporary Structures


A new chapter 14 provides guidelines for marking and/or lighting temporary structures, including construction equipment, cranes, derricks, drilling rigs, etc. The chapter outlines standards for using flags, paint and obstruction lights.

  • In addition to or instead of paint, obstacles over 200 feet AGL may utilize medium intensity white obstruction lights to increase daytime visibility.
  • Do not use high intensity lights on temporary structures.


The FAA also outlines how to mark or light container cranes, crawler cranes and tower cranes.

4. Line Spacing for Catenary Marker Balls


The FAA added a figure depicting the line spacing for catenary markers when adjacent lines are greater than 200 feet (61 meters) away. Please see figure A-23 on page 96 of FAA AC 70/7460-1M for more information.


5. Lighting During Wind Turbine Construction


Once a turbine under construction reaches 200 feet (60.9 m) in height, mark it with temporary lighting until construction is complete and the permanent lighting system replaces it.


Use a steady-burning L-810 to light the structure during the construction phase, if the permanent L-864 flashing-red lights are not in place. As the structure’s height continues to increase, relocate the temporary lighting as shown.


  • If power is not available, light turbines with a self-contained, steady-burning solar LED red light that meets the photometric requirements of an FAA L-810.
  • Using a NOTAM instead of lighting turbines is prohibited.

Questions on FAA lighting? We’re happy to help!