Verizon 700 MHz LTE cell site is latest victim of interference from fluorescent lights

High-frequency radio emissions from fluorescent lights installed in a Los Angeles office building are allegedly interfering with a Verizon Wireless (NYSE:VZ) cell site, prompting the FCC to referee the dispute between Verizon and the building owner.

In a citation and order released on Feb. 7, the FCC cited Brookfield Office Properties for operating industrial, scientific and medical (ISM) equipment that causes harmful interference at the Ernst & Young Plaza building, an L.A. high rise.

The offending ISM equipment, according to the FCC, involves two-lamp GE UltraMax fluorescent ballasts installed at the building. The ballasts are the same ones pinpointed as interfering with an AT&T 700 MHz LTE cell site in San Antonio, Texas, last year.

The FCC said agents from its Enforcement Bureau's L.A. office visited the Ernst & Young Plaza building on April 30, 2013, and informed the building manager that the light fixtures' radio emissions were likely interfering with a nearby Verizon 700 MHz LTE cell site. The building manager, said the FCC, replied that Verizon had already contacted Brookfield and that a lighting contractor was investigating the problem.

The agents came prepared with product documentation, providing the building manager a 2012 product bulletin from GE Lighting stating that certain two-lamp GE UltraMax ballasts were "tested in accordance with applicable FCC Part 18 requirements" but a small number were later found to produce "unintentionally high-frequency radio emissions that have the potential to cause interference with certain types of wireless communications."

According to Christopher Augustine, spokesman for GE Lighting: "Once we determined the cause of the interference, we immediately decided to recall all unsold, uninstalled ballasts to correct this potential issue. For those already sold and installed, GE provided steps to identify the affected ballasts by product and date code, and we provided instructions on how to exchange the units at no cost to the customer."

The FCC issued a warning letter to Brookfield on May 7 advising it to investigate the GE lighting ballasts and provide the bureau's L.A. office with an interim report within 30 days and a final report within 60 days. As of last week, the FCC said it had received neither report.

In late November 2013, the FCC's agents conducted their own investigation to confirm that "radio emissions on Verizon Wireless' licensed 700 MHz frequencies were emanating from ceiling fluorescent lights/ballasts" inside the building. In addition, they verified that the lighting fixtures are those covered by the GE Bulletin.

The citation issued last week gives Brookfield 30 days to file with the FCC's L.A. office an interim report on the investigations and corrective measures it has taken to eliminate the harmful interference, as well as a timeline for any pending corrective actions. A final report is due within 60 days of the citation's release date. Alternatively, Brookfield has the option of challenging the FCC's findings within 30 days of the citation's release.

"While rare, there have been a few occasions where the FCC issued a citation and order to spur a building owner to correct the ballast issue or face substantial fines," said GE's Augustine.

"GE is committed to providing support to our customers, the FCC and the affected cellular companies to assist in the correction of cellular disruptions when our fixtures are found to be the cause. We continue to cooperate as necessary with all available resources to ensure this support," he added.

For more:
- see this FCC document

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