WASHINGTON, Oct 15 (Reuters) - The Federal

Communications Commission said Tuesday it is opening a formal

inquiry into the use of data caps by telecom firms and how they

impact consumers and competition.

"For most people in the United States, rationing their

internet usage would be unthinkable and impractical. But, for

millions, limitations on how much data they can use online is a

constant concern," said FCC Chair Jessica Rosenworcel, noting

caps "can cut off small businesses from their customers, slap

fees on low-income families, and prevent people with

disabilities from using the tools they rely on to communicate."