About two dozen Dukes County workers have until Oct. 30 to show they are fully vaccinated or apply for a legal exemption, under a newly-enacted vaccination mandate modeled on the one approved by West Tisbury’s select board last month. It covers county employees, interns, volunteers and contractors who regularly work in municipal buildings.

County commissioners discussed the mandate last week and approved it unanimously at a special meeting Monday. It covers all workers who can enter a county workspace on their own, without having to be admitted, county administrator Martina Thornton said.

In the courthouse, the mandate pertains only to workers in the Dukes County Registry of Deeds office, she said.

Ms. Thornton had proposed a policy requiring unvaccinated county employees to come to work masked and prohibiting them from eating or unmasking unless they are alone in their own offices, but last week commissioners insisted on a stronger stance.

“My older brother had polio. Polio is no longer around for a reason,” commissioner Tristan Israel said. “I am supportive of mandates for vaccines because it’s for the greater good. This virus would have been more containable if people had acted more collaboratively, cooperatively, as a community.”

Commission chairman Christine Todd said differences of opinion over vaccines should not hold sway over public health.

“The gravity of this pandemic outweighs philosophical differences,” Ms. Todd said.

Martha Kane, a senior clerk in the registry of deeds, joined the meeting by phone to plead for a strict vaccine policy.

“My workplace is not fully vaccinated [and] we do not have separate offices,” she said. “I . . . implore you to take this seriously. I’m vaccinated, but Delta’s different.”

County employees seeking medical or religious exemptions to the mandate will have their cases reviewed by county counsel after submitting requests through Ms. Thornton, according to the mandate.

The county commission also heard a report from Vineyard Steamship Authority governor Jim Malkin on boat line affairs.

As the boat line prepares its budget for the coming year, Mr. Malkin said he expects no rate increase. Proposed ferry schedules for summer and fall 2022 are being reviewed by the port council and board of governors this month, Mr. Malkin said, along with a request for proposals from commercial freight boat operations to move sewage or garbage from the Vineyard to New Bedford or another off-Cape port.

“Hopefully there’s a commercial carrier that would come forward with a proposal to do this,” he said, calling it a way to ease traffic congestion in Woods Hole.

Mr. Malkin also discussed the change orders that have added millions to the cost of the Woods Hole terminal overhaul, describing in some detail the technical problems that have plagued the marine construction and engineering side of the project, pushing up costs.

On the land side, the new terminal is intended to have net-zero energy use, Mr. Malkin said, with geothermal and solar energy systems.

Electric buses, funded partially by grants, are expected next spring and the SSA is looking at a solar canopy for its Thomas Landers Road parking lot, he also said.

Asked whether the boat line is considering an employee vaccine mandate, Mr. Malkin said he wasn’t aware of any conversations on the subject but that any such requirement would have to be negotiated through the maritime unions that cover vessel workers.