Manufacturer had warned that office building lights might generate excessive radio noise.

As an environmentally responsible citizen, you probably know more than you want to about light bulbs: incandescents, fluorescents, compact fluorescents, LEDs, and plenty of variations on each. You might have sympathy for the people who handle commercial lighting, who have to worry about all of these types, and many more – and who have to worry about the FCC as well.

Last year we reported on two cases, this one and this one, about FCC actions against users of commercial lighting that caused interference to cell 4G data service. In both cases, so far as we can tell, the fixtures were conventional fluorescents that produced radio noise unintentionally.

The FCC has now presented us with a variation on the theme. The fixtures here – “fluorescent lighting electronic ballasts” – are located in a large office building on South Figueroa in downtown Los Angeles. They’re a specific kind that generate radio-frequency energy on purpose. Ideally the radio waves would stay trapped inside the device, but in practice some always leak out. Unlike most of the fixtures in our kitchens at home, this type is subject to specific FCC technical rules that limit the strength of escaping radio-frequency emissions. At 4G frequencies (and most other frequencies as well), the permitted levels are harmlessly low.

This time, though, the levels were high enough to cause interference to a nearby Verizon Wireless 700 MHz LTE cell site.

Verizon traced the problem to particular lights in the building and notified the building management. When the interference persisted, Verizon called in the FCC. The lighting manufacturer, GE, had previously issued a bulletin noting that some of its units produced excessive radio-frequency emissions. The FCC confirmed which units in the building were causing the trouble, found they were among those covered by the bulletin, and ordered the management to take corrective action. In practice, this typically means replacing the lights.

While the building management has to deal with that expense and disruption, it seems to us that the ultimate responsibility should lie with GE which, after all, shipped devices that admittedly failed to comply with FCC rules. But we commend GE for issuing the bulletin owning up to the slip, an action that may have helped to more quickly identify the problem units. If all manufacturers were this forthcoming about their mistakes, the task of chasing interference would be a lot easier. GE might be immune to FCC enforcement, due to the statute of limitations, but if not, we hope the FCC gives them credit for honesty and goes easy.