How much space do you need for a safe meeting? North Andover’s town moderator has an app for that.

North Andover Town Moderator Mark DiSalvo at the podium during a past town meeting.

In preparing for this year’s annual town meetings, local officials across the state are grappling with the unusual task of finding sites where they can keep participants safe during a pandemic.

Now a new online tool developed by North Andover Town Moderator Mark DiSalvo is helping remove some of the guessing from those decisions.

The digital calculator (safe-meeting.org) provides users a figure for the area size they need for an event based on the number of people attending and the safe radius for each person that planners conclude is needed for safe distancing.

While he created the Safe Meeting tool for his use and that of other town moderators, DiSalvo said it can help anyone seeking to safely manage gatherings during the COVID-19 crisis, including at workplaces, schools, places of worship, and athletic venues. The calculator is available free for anyone to use.

“We all forgot how to do math after we took our 10th grade SATs,” DiSalvo said. As a result, he said it is not easy for most people to readily calculate the space needed at events to meet safe distancing standards.

The “plug and play” calculator not only addresses that need but allows users to go beyond the US Centers for Disease Control and Prevention guideline that calls for keeping people 6 feet apart, according to DiSalvo, who said he did not consult with public health experts before launching the tool because it is based on those federal standards.

DiSalvo, who owns a private equity fund management firm, developed the equation behind the calculator. The brothers Rich Kaufman — a North Andover resident and friend of DiSalvo — and David Kaufman of Lynnfield then wrote the code.

When he provided the tool to fellow moderators, DiSalvo got positive feedback and encouragement to make it available for other uses.

“I sent it to many of my clients — banks, portfolio companies —and some of them began utilizing it and forwarding it to others,” DiSalvo said.

He also sent it to municipalities, and to emergency management and public health agencies in many states, and some of them are using and sharing it. DiSalvo said he even learned someone from the CDC sent the tool to a New Hampshire city official.

DiSalvo heads a small informal team of volunteers overseeing the not-for-profit initiative. One team member, Seerena Blum, created the Safe Meeting website while another, Kyra Brown, created a video.

Team member Bernie Zelitch, a software engineer and musical composer, said he was inspired to join the group because “I appreciate elegant things done simply to solve an important problem.”

“Everybody is going to need something like this whether they are planning bridge club meetings, church services, or concerts,” he said.

Most Massachusetts towns postponed their annual meetings to June or later due to the pandemic, so many are now deciding where to hold them. DiSalvo said to enable the maximum number of participants to safely attend his town’s annual meeting on June 16, DiSalvo selected an outdoor site — the high school football stadium — and two adjacent fields for the event.

Manchester-by-the-Sea Town Moderator Alan Wilson used the Safe Meeting tool in selecting the Manchester Essex Regional Middle High School football field as the site of his town’s June 22 meeting.

“I found it very helpful,” he said. “It makes it simple to calculate the numbers.”

DiSallvo said for average citizens, he hopes the calculator can serve as a “wake-up call about how much space you actually need as a minimum for people to be safe.”

John Laidler can be reached at [e-mail].