Three public-safety organizations and CTIA, the trade association for commercial wireless carriers, this week asked the FCC to address the use of low-power devices in the 700 MHz band—specifically, wireless microphones—that could interfere with first-responder communications in the band.

In a letter to Acting FCC Chairman Michael Copps, CTIA and the public-safety organizations—the National Emergency Number Association (NENA), the Association of Public-Safety Communications Officials (APCO) and the National Public Safety Telecommunications Council (NPSTC) urged the commission to “take action to curb the harmful use of these low-power devices.”

NPSTC Chairman Ralph Haller said the purpose of the letter was to ensure that the FCC is aware of the concern, but he acknowledged that finding a method to rid the 700 MHz band of wireless microphones would be difficult.

“I don’t have a good answer for that, because there’s no database of who the users are or where the microphones are,” Haller said during an interview with Urgent Communications. “Therefore, you can’t do a letter campaign and say, ‘Be off of these frequencies in six months.’”

Thousands of entities—schools, hotels, playhouses, churches and other venues throughout the country—use wireless microphones that operate on the same 700 MHz frequencies that the FCC has allocated for public-safety use, Haller said. Unless the matter can be resolved, the low-power microphones can interfere with public-safety communications in the band within a small geographic area, while the high-power public-safety systems promise to interfere with wireless microphones throughout a much larger area, he said.

“There’s not an easy answer for it, but the commission needs to be aware of it,” Haller said. “If there are cases of interference to public-safety systems, the commission needs to go in and do enforcement action and issue forfeitures to make people aware that you can’t just put something on the air and use it.”

In the joint letter, the public-safety organizations and CTIA ask the FCC to approve an order clarifying that “low-power auxiliary devices must not interfere with authorized public safety and commercial licensees, and that those devices must accept all interference from licensed users.” They also ask that such devices cease operating within one year of such an order being adopted. The letter also calls for a ban on the sale of such devices operating in the 700 MHz band.

“Decisive commission action to halt additional unauthorized users will ensure that critical public safety systems and the commercial systems that carry emergency calls are unhindered by interference,” the letter states.

If the FCC takes such action, Haller expressed empathy for the users of wireless microphones in the 700 MHz band.

“They didn’t know that their use of these microphones is actually illegal,” he said. “I feel bad that these people have bought these [microphones] and now they’re faced with having to do something.”