Gaming regulators on Thursday weighed health and safety protocols they could impose on casinos to limit the risk of exposure to the coronavirus when they reopen, possibly by June 29.

Massachusetts Gaming Commission staff presented the commission with three sets of increasingly comprehensive minimum guidelines focusing on social distancing, hygiene, safety and reporting measures for Plainridge Park Casino in Plainville, MGM Springfield and Encore Boston Harbor in Everett, all of which have been closed since March 15.

The Investigations and Enforcement Bureau recommended that the commission require that each of them work with a public health expert or epidemiologist to develop a detailed plan the casino would submit to the commission at least a week before reopening.

The plan would outline the steps it would take to comply with the guidance issued by the federal Centers for Disease Control and Prevention, the state Department of Public Health, Gov. Charlie Baker’s orders and the guidelines the commission ultimately adopts.

The commission did not make any decisions Thursday, but its members were in consensus that masks should be required for players, in keeping with Baker’s order.

They wanted to think more, however, about possible exceptions, like when a gambler is drinking a beverage.

There also was consensus that each facility should make hand sanitizer available at every entrance, though there was not unanimous agreement on whether the casinos should encourage or require players to use it.

“The challenge might be that it eventually permeates down to the public adhering to a lot of these guidelines,” said Commissioner Enrique Zuniga.

Commissioner Bruce Stebbins said patrons should know even before they arrive that their temperature probably will be checked and they should be able to answer questions such as whether they have had any symptoms or have had any contact with someone who has.

“That will help ease the flow of patrons into the facility and kind of prevent any unnecessary backups,” Stebbins said. The commission has been studying reopening plans in other states and countries.

Commission officials said Thursday that its rules will not be the only ones the casinos will have to adhere to; the Baker administration is working on its own set of guidelines as well, they said.

A spokesman for Baker said hotels affiliated with the casinos may reopen in the administration’s current phase – phase 2. Restaurants may open for outdoor dining in the first step of phase 2 and may open for indoor dining in the second part of the phase.

The horse racing track at Plainridge Park, casino gaming floors, and theaters and arenas within casinos will open later.

State House News contributed to this report.