The U.S. Coast Guard has issued an alert to mariners that it has received reports of onboard LED lighting interfering with VHF reception, causing a potential safety hazard by affecting a vessel’s radio-telephone, digital selective calling (DSC) and automatic identification systems (AIS).
The alert reports that ships in different ports have experienced degradation of the VHF receivers, including AIS, caused by their LED navigation lights. LED lighting installed near VHF antennas has also shown to compound the reception. In one example, a maritime rescue coordination center in port was unable to contact by VHF radio a ship involved in a traffic separation scheme incident, and the ship also experienced poor AIS reception.
Strong radio interference from light-emitting diode sources – such as navigation lights, searchlights and floodlights, interior and exterior lights, and adornment – may not be immediately evident to maritime radio users, the Coast Guard warns. It advises testing for the presence of LED interference by taking the following steps:
According to manufacturer Hella Marine, all electronic devices give off some level of electro-magnetic interference (EMI). “The danger comes when this interference occurs in the frequency range between 156 MHz and 165 MHz, used by marine VHF and AIS systems,” the company stated in a news release regarding the USCG alert.
Regulatory authorities have created specific maritime navigation and radio communications equipment standards for LED lighting used on boats. When refitting lights, look for lamps that meet maritime EMI standards.
The USCG has asked that those experiencing this problem report it to at www.navcen.uscg.gov. Select “Maritime Telecommunications” on the subject drop-down list, then briefly describe the make and model of LED lighting and radios affected, distance from lighting to antennas and radios affected, and any other information that may help illuminate the scope of the problem.