The Coast Guard appealed to Cuba yesterday to accept the provisions of international treaties on safety at sea while the Justice Department made public the criteria it is using to seize boats engaged in bringing Cuban refugees to south Florida.

Charging that Cuban authorities are forcing some boat owners to over-crowd their vessels with too many refugees, the Coast Guard commandant, Adm. John Hayes, said, "Cuba is a party to the international convention for the safety of life at sea. Yet thousands of refugees in the current 'Freedom Flotilla' are encouraged to leave the country in overcrowded, unsafe vessels."

Hayes cited the vessel "Dr. Daniels," which was forced to accept 600 passengers when it had safety equipment for 296.

"Dr. Daniels" is one of four boats seized by government authorities since the boatlift of Cuban refugees began more than two weeks ago.

Justice Department officials said the criteria being used in deciding whether to seize boats are the safety of the vessels, whether there are large numbers of Cubans aboard, and whether the boat owners are engaged in profiteering.

They said the criterion on number of Cubans aboard a vessel was aimed less at slowing the flow of refugees than at preventing the overcrowding of small boats.

The officials also said that refugees aboard some boats are being interviewed after they arrive at Key West, Fla., to determined whether they were charged exorbitant fees for the passage.

All boat owners carrying refugees are routinely being given citations that give the government the option to fine them $1,000 per refugee. But administration officials have indicated that the fines will be leveled only against operators of unsafe boats and those using the refugees to profit.

In other developments yesterday:

President Carter's Democratic presidential rival, Sen. Edward M. Kennedy (Mass.), announced that the Senate Judiciary Committee, which he heads, will hold a hearing on the refugee problem Monday. "The chaos and confusion in the Cuban and Haithan refugee crisis is matched by the chaos and confusion in the administration's policy," Kennedy said.

State Department spokesman Hodding Carter scoffed at a report that Cuba intends to demand negotiations toward normalization of U.S. relations in return for granting passage to about 400 Cubans who have taken refuge in the U.S. diplomatic mission in Havana. Carter said he knew of so such demand, adding that "the notion of using the bodies of these people to effect some change is abhorrent."