The Federal Home Loan Bank Board conditionally approved deposit insurance yesterday for John Hanson Savings and Loan, a step that should significantly ease depositors' fears and reduce the potential liability for Maryland as it grapples with a continuing thrift association crisis.

"I'm sitting on cloud nine," said Hanson president Jerry D. Whitlock after federal officials informed the $630 million Beltsville-based thrift by telephone that Federal Savings and Loan Insurance Corp. protection had been conditionally approved.

Douglas H. Green, a bank board spokesman, said the conditional grant "virtually guarantees" that Hanson will obtain final FSLIC approval by the end of August. "We would not grant conditional insurance if we didn't think John Hanson was viable," Green said.

In addition to easing the worries of state officials who are anxious for all Maryland thrifts to obtain federal insurance, the bank board's action should go far toward reassuring Hanson's 65,000 depositors, Whitlock said.

Since mid-May, when reports of mismanagement at one Baltimore thrift sparked runs at several savings and loans and prompted Gov. Harry Hughes to impose a $1,000-a-month withdrawal limit per customer at Hanson and other institutions, Hanson customers have withdrawn $35 million from their savings accounts, Whitlock said.

"We're trying now very diligently to get that federal insurance seal on our windows so that we can get our savers back on track," Whitlock said. John Hanson has 23 offices in an area stretching from Frederick County to Baltimore to the Washington suburbs and the Eastern Shore.

"It's a real shame this whole thing had to happen," Whitlock added, referring to the crisis of confidence that is still shaking many segments of Maryland's $10 billion thrift industry. "All it took was a couple of bad apples . . . that the industry, the regulator and the insurer were unaware of."

John Hanson, which until yesterday was the second largest thrift still insured by the state, must raise $15 million to satisfy the federal requirement that a thrift's assets exceed liabilities by 5 percent, Whitlock said.

Hanson has $13 million in readily accessible cash but needs a total of $28 million. To raise the balance, Whitlock said, Hanson plans to sell or issue additional stock or ask the state to issue "net worth" certificates, which in effect are IOUs to the government that Hanson could use to improve its cash position.

The Maryland Deposit Insurance Fund, the insurer of those savings and loans that do not have federal insurance, has promised to issue certificates of up to $11.4 million to Hanson to enable the association to win FSLIC protection, Whitlock said.

MDIF Director Frederick L. Dewberry hailed the bank board's action as "extremely encouraging" and said his agency was working with other large thrifts to help them obtain federal insurance.

One of those, First Maryland Savings and Loan of Silver Spring, with more than $400 million in assets, has had difficulty raising cash to meet the federal "net worth" requirement, according to state officials and industry experts.

Less than a month ago, in response to an inquiry from state Del. Gerard F. Devlin (D-Prince George's), Dewberry wrote, "I can tell you that they First Maryland are a long way from FSLIC approval at this time."

First Maryland president Julian M. Seidel has said he is confident that his association will eventually obtain FSLIC protection. Meanwhile, the thrift has ample cash on hand to meet the day-to-day needs of customers, Seidel has said.

Community Savings and Loan, a $640 million thrift in Montgomery County, is widely believed to be in a position to qualify for FSLIC insurance. Another Montgomery thrift, Friendship, with more than $300 million in assets, has been targeted for purchase by Chase Manhattan Corp. of New York.