Evan Schuman's StorefrontBacktalk

With so many consumer devices using the same wireless frequencies, it was bound to happen: Just before Christmas, a U.K. family in a village 50 miles southwest of London lost the use of all wireless devices—everything from key fobs for unlocking vehicles to a wireless thermostat and a digital shower—until the problem cleared up without explanation several days later. The BBC reported that faulty wireless equipment had caused similar incidents in the past, including a street in northern England of homes whose wireless was jammed in 2010 by handheld wireless devices used to take orders at a nearby restaurant.

Retailers get understandably worried about customers who might intentionally or unintentionally block store Wi-Fi that’s used for POS, associates’ handheld devices or free customer wireless service. But there’s a risk the other way, too—the newest Wi-Fi access points have a range of more than 200 feet indoors and 800 feet outdoors. That’s easily enough to jam neighboring stores’ Wi-Fi in a mall or interfere with homes near a standalone store. Unfortunately, there’s no easy way to know whether a store’s Wi-Fi is causing problems in the neighborhood—at least not until the FCC shows up to investigate a complaint.