MONTPELIER, Vt. – A report commissioned by the Vermont Legislature on the potential threat to human health posed by smart meters, the devices used by electric utilities to measure power consumption and ultimately save energy, found the devices emit only a small fraction of the maximum exposure levels set by the Federal Communications Commission.

The maximum peak radio frequency level measured one foot from a meter was 3.9 percent of the FCC’s top exposure limit, said the Department of Public Service, which hired the Washington state company that prepared the report.

The smart meter exposure compared with a limit of 1 percent of the radio frequency exposure level for a cordless phone, 6.5 percent for a microwave oven and 10.5 percent for a cellphone.

“It is concluded that any potential exposure to the investigated smart meters will comply with the FCC exposure rules by a wide margin,” said the report, released Wednesday.

The conclusions were based on results of lab testing and field measurements from smart meters being used by Green Mountain Power and the Burlington Electric Department.

Green Mountain spokeswoman Dorothy Schnure said the new smart meters, and other technological improvements, would improve reliability and help the utility offer more cost-effective service to its customers.

“The results of this study confirmed what we already believed: Smart meters are safe for our customers,” she said.

A number of Vermont utilities are installing smart meters in place of traditional meters that had to be regularly read by someone to determine a customer’s power consumption. Smart meters allow two-way communications between the customer and the utility, in many cases by two-way radio.

The meters could make it possible to allow electricity prices to vary at different times of the day, which could encourage consumers to use power-hungry appliances such as dishwashers and clothes dryers at night when demand, and the price, is low.

But some fear the meters could have unintended health effects because of human exposure to radio frequency levels from the meters.

The group Vermonters for a Clean Environment has been skeptical of smart meter technology. No one from the organization responded Wednesday to a request for comment about the new report.

A number of states, including Maine, allow customers to opt out of having smart meters installed on their home or business, but they are charged a fee. Last year, Vermont passed a law requiring the utilities to pay the cost when customers opt out.