(Image Credit: Toby Talbot/AP Photo)

Are "smart" meters safe? Or do these wireless devices, which use radio waves to report consumers' electric consumption to utilities, pose a threat to health?

Such questions have been debated widely in California and other states. Yet, to date, no state's public utility commission has held public hearings on the question or conducted its own safety investigation. Now Maine's is poised to do so.

So widespread are fears about the devices' safety, according to the anti-meter Naperville Smart Meter Awareness group in Illinois, that three states have instituted moratoriums on them. In others, anti-meter, class-action lawsuits are pending. In California, says the group's website, 47 municipal jurisdictions have either demanded a halt to installations or have criminalized them.

The Maine Public Utilities Commission voted Tuesday to investigate the safety of Central Maine Power's "smart" meters, 615,000 of which have been installed in homes throughout the state at a cost of $192 million, according to Smart Grid Today, an online journal that tracks the power industry.

The public utility commission vote followed a Maine Supreme Judicial Court ruling two weeks ago that instructed the commission to resolve safety concerns about the meters, according to The Portland Press Herald. Under Maine law, says Bruce McGlauflin, an attorney representing worried Maine utility customers, the commission must ensure that utilities provide safe service.

Exactly how the commission will do that remains to be seen. "It's been left to their discretion," McGlauflin said.

"Smart" meters produce radio-frequency emissions similar to those produced by cellphones, he added.

Some people, including some of his clients, believe they have a heightened sensitivity to the emissions and blame them for migraines, sleeplessness and other physical or mental illnesses.

Dan Richman, a Smart Grid Today reporter, says utility commissions in California and other states have addressed the safety question by conducting reviews of scientific literature. The result of such reviews, he says, has been uniform: "The literature concludes the meters are safe."

In 2010, the California public utility commission, in rejecting what it called an unreasonable request to investigate alleged health impacts further, noted the meters' emissions were one six-thousandth of those permitted by federal health standards. The World Health Organization stands virtually alone in calling them a potential carcinogen.

No commission has held hearings; nor has any attempted its own original research. For Maine to take either step, Richman says, would be a first.

He doubts that Maine will attempt research because that would be costly. "The most sophisticated research project into RF emissions ever conducted in the U.S. is still going on," he wrote Wednesday on Smart Grid Today. "The $24 million, multiyear study by the National Institutes of Health is still about two years away from completion."

The director of the study told Richman it might be extended to include "smart" meters, he said.

A hearing is Maine's more likely option, Richman says.

If "smart" meters are safe, why are so many people afraid? "A certain segment of the population is highly phobic," he said.

"But I don't want to be the one to say there's nothing behind this, because we don't know to an absolute certainty. It's very hard to prove a negative."