Commissioners approved the rules by a 5-0 vote.
Encore Boston Harbor, MGM Springfield and Plainridge Park have been closed since mid-March. No reopening date has been set, and casino operators say they will need 10 to 14 days notice in order to ramp back up.

“We wish our licensees great success when the reopening is permitted,” commission Chairwoman Cathy Judd-Stein said. “To each licensee, I thank you for your patience today.”

The requirements were approved after a nearly two-hour meeting and weeks of preparation.

The sweeping guidelines include rules and recommendations for screening guests, including a requirement to make hand sanitizer available and a suggestion to conduct temperature checks. Social distancing guidelines for slots include a requirement that casinos turn off every other slot machine and remove chairs, and to either ensure a minimum of 6 feet between slot positions or install 6-foot-tall plexiglass dividers.

There are also reduced occupancy limits based on a formula for total patrons and employees. Commissioners believe the formula will reduce each facility’s capacity to about 25%.
The casinos’ opening date depends on Gov. Charlie Baker’s reopening plan, and is expected to occur in Phase 3. The state is in what officials have called the second part of Phase 2.

The administration has said it will review two weeks of public health data from the start of indoor dining — which began June 22 — before launching Phase 3, meaning the decision is not likely until at least July 6.

Other minimum requirements for the reopening included:

    -Must comply with all guidance and protocals issued by local, state and federal governments and agencies.
   - Must develop a communications plan for informing guests of its COVID-19 precautions.
    -At all significant points of entry and exit, separate ingress from egress in order to avoid two-way guest traffic flow.
   - Casino staff to sanitize operating slot machines and chairs as frequently as possible between player turnover and at regular intervals, at a minimum of every 4 hours.
    -Signage at each point of entry and at prominent locations throughout the gaming area to remind guests of safe practices including frequent hand washing, use of hand sanitizer, proper wearing of masks, and to go home if sick.