The first Massachusetts dance to be starting up in person indoors is the Worcester dance:
https://www.worcesterdance.org/. They list:
"Documented proof of either full vaccination or a negative COVID test. The COVID test must be taken no more than three days prior to the dance. Photos of either vax cards or said test results will be accepted as proof.
Per City of Worcester mandate, masks are to be worn at all times by everyone in the building.
Each attendee must provide their name, email address, and cell phone number for contact-tracing purposes.
The gymnasium where the dance is being held is quite large for the expected number of attendees. We will augment that by placing box fans in front of open windows in at least two locations to provide for the circulation of fresh air. The facility also has several ceiling fans which will assist in that process."
Jeff