Administrator Kenneth Feinberg delivers an opening statement at The One Fund town hall meeting at the Boston Public Library. (Yoon Byun/AP)

Everyone killed or injured in last month’s Boston Marathon bombings will receive some compensation from the $30 million in donations pledged for victims so far, according to a formula released Wednesday morning by the administrator of the One Fund Boston.

The protocol, issued by Kenneth Feinberg, lists no specific dollar amounts because money is still trickling in, Feinberg said in an interview. But it sets up four categories of injuries, reserving the largest amount of compensation for the families of the people killed, double amputees and those who suffered permanent brain damage.

The next category is for people who lost a single limb, followed by those who required overnight hospitalization and, finally, those who were treated as outpatients. No money will be offered for those who suffered psychological trauma, Feinberg said, because there isn’t enough in the fund to cover them.

Unlike compensation awards offered after the Sept. 11, 2001, terrorist attacks on the World Trade Center and the Pentagon, and the 2010 Deepwater Horizon oil spill — both of which were determined by Feinberg — victims do not have to waive their right to sue for injuries. The One Fund money is considered a gift, and its guiding principle was to speed emergency money to those who need it, Feinberg said.

“There is no connection to the tort system,” said Feinberg, a lawyer in Washington. “You don’t waive your rights. It’s a gift. You have much more flexibility in establishing rules.”

Income won’t be a factor in the awarding of One Fund money — unlike when Feinberg, when disbursing $7 billion in compensation after the Sept. 11 attacks, was compelled to compare how much busboys and financial workers might have expected to earn over their lifetimes.

Payments for people who were hospitalized will differ depending on length of stay, Feinberg said.

The bombings near the finish line of the Boston Marathon killed three people and injured more than 260. A police officer for the Massachusetts Institute of Technology also was killed during the manhunt for two suspects, brothers Tamerlan and Dzhokhar Tsarnaev. Tamerlan Tsarnaev, the elder brother, was killed in a shootout with police. The younger Tsarnaev is in custody.

According to its Web site, the One Fund has received nearly $12.5 million in public pledges and $17.6 million in corporate pledges. Dozens of funds have also been established for individual and small groups of victims.

Efforts to reach bombing victims and their families Wednesday about the protocol were unsuccessful. Larry Marchese, a spokesman for the family of Martin Richard, an 8-year-old boy killed in the attack, said in an e-mail: “I do not expect the family will make any public statements until they eventually thank the public for supporting all of the victims of the Marathon bombing.”

The major difference between the final set of rules and a draft plan Feinberg outlined in public hearings with victims and others last week is the fourth category, which will offer some compensation to victims treated as outpatients for injuries such as lacerations and broken bones. Feinberg said the awards to those people will be “modest.”

Victims have until June 15 to file a claim. In the ensuing two weeks, they will have the right to meet with Feinberg to discuss their proposed award. Checks will begin to go out June 30, and the money should be distributed within a few days, he said.

“I believe it will be a very emotional, trying period over the next six weeks,” said Feinberg, who has also run victim compensation funds in the aftermath of mass shootings at Virginia Tech in 2007 and in Aurora, Colo., and Newtown, Conn., last year. There will be “very emotional, very angry, very frustrated people. It goes with the territory.”

Even now, with doctors still struggling to save some victims’ limbs, the number of single and double amputees is uncertain. Feinberg said there might be as many as 20 amputees by June 30, some of them double amputees.

As for those scarred psychologically, he said, there simply wasn’t enough money in the charity fund to help.

“Absolutely, it is worthy,” he said. “The law accepts it. Existing tort law condones it. The fact of the matter is, when all you have is $30 million, it’s not enough.”