It’s a trend that’s increasing, say Franklin Regional Council of Governments officials: AirBnB Vacation Rentals by Owner, and short-term rentals via FlipKey and HomeAway.

With a determination by the state Department of Public Health that such online rental operations, like other rentals, need to comply with requirements to sure there’s a potable water supply, safety inspection and — where applicable — sanitary kitchen facilities, the COG is hosting a workshop for town officials Thursday, from 6 to 8 p.m., at the John W. Olver Transit Center.

The regional health and building inspector, as well as Franklin Regional Planning Director Margaret Sloan and Regional Building Commissioner Jim Hawkins will discuss current zoning bylaws, the building code and the sanitary code as they pertain to short-term rentals, and the best ways towns can oversee licensure and inspections, along with the regulatory options for towns and the steps for hosts who want to come into compliance.

“We want to make sure that everyone understands, ‘What does the building code have to say if you’re going to rent out a property like this, and how is that different whether you live there or not?’” says Phoebe Walker, the COG’s director of community services. “What do the sanitary codes believe an AirBnB is? And what are the best practices around zoning for this? It’s a new aspect of our communities.”

Walker estimated that there are 1,000 such rental operations around the county. Many of them need to be licensed to comply with the stipulation of AirBnB and other operations that they comply with local codes.

“Right now, they’re all mostly flying under the radar,” she added. “A few towns have reached out to every short-term rental, because according to the state Department of Public Health, they are B and Bs, and there are sanitary codes to protect the liability of the owner and the public health of the visitor.

Under the proposed state food code, smaller operations with six or fewer guest rooms won’t have to have food training or have food service certification.

While the workshop is intended for local officials, Walker said, it’s assumed that some people who have short-term rentals will also attend and learn the steps they should take to comply with requirements, which also are expected to change under a new state building code that will take effect Jan. 1 as well.

There are also zoning issues that towns may also want to consider to assure that there are limits on the scale and potential impacts of the vacation rentals.

With the number of such rentals increasing as a way for residents to earn money on unused space in their homes, the issue arose because existing bed-and-breakfast operations have seen their business shrink.

“It just isn’t a level playing field,” said the COG’s regional health agent, Glen Ayers, adding that the building inspector has also raised questions of whether the use is permitted under town zoning.

“Mostly, this is on a voluntary compliance basis,” Ayers said. “We’re trying to encourage people, for the sake of liability, that it’s worth it to be able to say that you’re fully licensed. It’s not a huge expense, and it’s not anything onerous.”