Couch potatoes of America, listen up. Congress may be just days away from turning down the volume on ear-splitting TV.

The Commercial Advertising Loudness Mitigation, or CALM, Act follows rules set last year by a United Nations body in Switzerland on how to measure and clip broadcast volumes. The U.S. bill, inspired by decades of consumer complaints, should finally ban TV ads that blare louder than the programs they interrupt.

California Democratic Rep. Anna Eshoo, who sponsored the bill, says it is the most popular she has pushed in her 18 years in Congress. "If I'd saved 50 million children from some malady, people would not have the interest that they have in this," she says.

When Washington first considered TV loudness in 1984, regulators said there was no objective way to quantify and control it. That left advertisers free to turn up the volume.

Arriving at standards to separate the deafening from the merely loud has required years of auditory analysis, mathematical modeling and international debate.