MSIB 30-18 (Attachment can be found at: https://homeport.uscg.mil/my-homeport/safety-Notifications/MSIB?cotpid=40&Source=https://homeport.uscg.mil/port-directory/delaware-bay)


Potential Interference of VHF-FM Radio and AIS Reception

The U.S. Coast Guard has received reports from crews, ship owners, inspectors and other mariners regarding poor reception on VHF frequencies used for radiotelephone, digital selective calling (DSC) and automatic identification systems (AIS) when in the vicinity of light emitting diode (LED) lighting on-board ships (e.g., navigation lights, searchlights and floodlights, interior and exterior lights, adornment).

Radio frequency interference caused by these LED lamps was found to create potential safety hazards. For example, the maritime rescue coordination center in one port was unable to contact a ship involved in a traffic separation scheme incident by VHF radio. That ship also experienced very poor AIS reception. Other ships in different ports have experienced degradation of the VHF receivers, including AIS, caused by their LED navigation lights.

You can find more information about this issue, the procedures to test for the presence of LED interference, and how to report problems with LED interference by reading Safety Alert 13-18 (attached to this MSIB) or by visiting the webpage below.

https://www.dco.uscg.mil/Our-Organization/Assistant-Commandant-for-Prevention-Policy-CG-5P/Inspections-Compliance-CG-5PC-/Office-of-Investigations-Casualty-Analysis/Safety-Alerts/



S. E. ANDERSON
Captain, U.S. Coast Guard
Captain of the Port, Delaware Bay