The digital “smart meters” that Central Maine Power Co. has installed at almost every home and business it serves pose no health threat, the staff of the Maine Public Utilities Commission has concluded.

The finding isn’t the final word on the issue, which has been debated for years, but it is a blow to activists who say the radio-frequency emissions from the meters and their wireless networks can be harmful to human health.

The finding is in a 67-page report by a PUC hearing examiner that was posted Tuesday on the commission’s website. The report will guide the commission, which ultimately must decide how to handle the protracted case involving the health issues, a subject of global interest. That decision is expected later this year.

Activists have until April 11 to dispute the examiner’s report. Bruce McGlauflin, a lawyer who represents the activists, said Wednesday that he plans to file objections by then.

The PUC staff didn’t specifically determine that the smart meters are safe, McGlauflin said, only that the system meets a set definition as a “safe, reasonable and adequate utility service” under Maine law. He agreed, however, that the finding is a setback for his clients.

“Sure, we would have liked the examiner’s report to agree with us,” McGlauflin said. “But it doesn’t preclude the commissioners from agreeing with us.”

In 2009, the PUC approved CMP’s plan to replace old-style analog electricity meters with digital smart meters for its 620,000 customers. Health activists soon objected, joined by residents who claimed that they suffered from various medical symptoms after the meters were installed. They appealed the PUC’s approval in court, arguing that the commission hadn’t met its legal obligation to ensure that the $200 million smart-meter program is safe.

In 2012, the Maine Supreme Judicial Court agreed with the activists and ordered the PUC to take a second look at the health issues.

The PUC doesn’t have the expertise to conduct its own health studies so it has relied on accumulated knowledge. It accepted thousands of pages of new testimony from experts across the globe. The case now encompasses more than 660 separate filings, with reams of written and oral testimony from expert witnesses on the connection between brain tumors and the use of cellphones, for instance, and from residents who link the meters with symptoms that include headaches and fatigue.

After reviewing the testimony, the PUC staff wasn’t convinced that the meters pose a health hazard.

It said that the scientific evidence presented in the case is inconclusive. It found no credible, peer-reviewed studies to show a direct health risk from smart meters. The studies that do show a risk are based on exposures to much higher radio-frequency levels, the staff noted.

The staff also determined that the radio-frequency emissions from the smart-meter network comply with federal safety standards, and that no state or federal regulatory body or health agency in the United States or Canada has found smart meters to be unsafe.

“By this finding,” the staff wrote, “we do not intend to diminish the concerns of (the intervenors) regarding the possible health impacts from (radio-frequency) emissions.”

The staff said it agreed with the World Health Organization and others that more research is needed, especially since radio-frequency-emitting devices are now so common.

In response to the report, Ed Friedman of Bowdoinham, the lead plaintiff in the 2012 Supreme Judicial Court case, said late Wednesday, “While not surprising the PUC staff continues to thumb their nose at the law … and show their bias in favor of utilities, it’s particularly egregious they rejected something like 800 peer-reviewed scientific references submitted to them as evidence.”

CMP declined to comment Wednesday on the finding, citing PUC rules against trying to influence the commissioners once the examiner’s report is released. It did, however, refer to several points in its testimony, including:

CMP’s system complies with the Federal Communications Commission’s safety standards for radio-frequency emissions.

As confirmed by field measurements, radio-frequency emissions from smart meters are well below those from other natural and man-made sources.

The health data on other wireless technologies, primarily cellphone data, does not suggest health risks at the level of radio-frequency emissions from smart meters

CMP’s smart meters’ emissions are below the levels recommended by the opposition’s expert witnesses in the case.

Since it installed the digital meters, CMP has used the technology to read meters remotely and speed service restoration after storms, among other things. Thousands of customers are using a smart-meter-enabled website to help manage their home energy use.

Only two of the three commissioners will decide the case. The chairman, Tom Welch, has recused himself because he did legal work on CMP issues while he was in private law practice.

McGlauflin said it’s not clear what the practical effect would be if the commission did rule in favor of the activists. Short of tearing out all of the meters and replacing them, he said, it’s possible that people who don’t want them at their homes could get analog meters without paying additional fees.

The 8,000 or so customers who have chosen to “opt out” of the smart meter program now pay $12 a month to cover the cost of alternative equipment and meter readings.

Tux Turkel can be contacted at 791-6462 or at:

[email protected]