The Federal Communications Commission said Wednesday that its commissioners voted unanimously in favor of a proposal to free up airwaves in the 5 GHz band of spectrum and promote the growth of fast, new WiFi technology.

The proposed rules follow a January announcement by FCC chairman Julius Genachowski at the Consumer Electronics Show, in which he said that allowing use of this band could free up WiFi congestion in areas with significant Web traffic.

The proposal would increase networks by 35 percent and would mark the largest release of unlicensed airwaves since 2003.

Electronics industry groups were quick to commend the FCC’s action, saying that opens the potential for new innovation.

Gary Shapiro, president of the Consumer Electronics Association, said he hopes the move will lead to better consumer access to data “whenever and wherever they want.”

The proposal has raised concerns among those who want the agency to tread carefully as it moves forward. Automakers have said that moving too quickly to open up the spectrum could hurt the development of smart vehicle technology.

The Intelligent Transportation Society of America, an advocacy group for transportation technology, said Wednesday that it acknowledges the FCC’s “desire to move forward expeditiously” but cautioned the agency about prioritizing consumer WiFi technology over connected-vehicle technology.

The National Telecommunications and Information Administration has also noted that some federal agencies, including NASA and the Department of Defense also use this band for communications.

The FCC has said it will work with all stakeholders on any potential issues as the proposal moves forward.