Consumer groups are demanding an investigation into alleged violations of Connecticut’s “free inflation air” law, according to TheDay.com.

During business hours, it’s illegal to require motorists to pay for air in Connecticut, the site reported, yet a growing number of consumers have complained of a growing number of coin operated air stations or locations that have refused to repair broken “free air” systems.

Paul Sanderson of Salem started noticing the paucity of stations offering free air when he started hunting for a gas station where he could keep his tires properly inflated. Some stations near his home displayed mangled air hoses that never were repaired, while others had converted to coin operation.

“That just seems wrong,” said Sanderson. “How much could air cost?”

Sanderson said he believes the environmental and safety benefits of keeping tires properly inflated should require stations to provide free air.

So he started hunting around the Internet and was surprised to find, as confirmed by Claudette Carveth, spokeswoman for the state Department of Consumer Protection, that free air is required by law in Connecticut.

In addition, retailers that sell at least 10,000 gallons of fuel a month – virtually all stations in the state – are required to post a sign in a "conspicuous location" stating that free air is available, Carveth said.

Stations are allowed to seek payment from coin-operated air compressors after hours, she said, but otherwise must offer free air.

Many longtime service-station owners support the law.

“It’s just a little something you can give back to the customer,” said Michael Olsen, owner of the Hess station in Waterford.

However, a check of about a dozen gas stations in the area shows that about half of the businesses fail to post adequate signage advertising free air. For instance, two gas stations on Route 161 in East Lyme recently added coin-operated air compressors without the required signage.

Others post confusing signs, Sanderson said, that leave consumers scratching their heads – and, presumably, feeding quarters into the machines when they might not have to.

Frank Greene, director of the Consumer Protection Department’s division of food and standards, said his agency actively checks gas stations for compliance with the free-air law, but also depends on consumer complaints. The state receives only about 10 complaints a year about stations not offering free air, he added.

That’s testimony to the fact the state needs to do a better job advertising the free-air law – to consumers and to businesses – said Carveth, the department spokeswoman.