The owners of a Silver Spring apartment building are being sued by Montgomery County for allegedly failing to follow steps in the county's condominium conversion procedure in order to circumvent new state laws with extensive tenant protections that go into effect July 1.

Many of the tenants in the four-story building on Sligo Avenue are elderly, and would qualify for special renting privileges, including life tenancy, under the new laws.

According to the suit filed in the Montgomery County Circuit Court, the Carone partnership, owners of the 43-unit Carona Apartments, did not file a mandatory property report before sending tenants notices that the building would be converted to condominiums.

The county charges that the landlord acted under the advice of counsel in moving quickly to send out notices and escape the effect of the new regulations. A provision of the state law exempts buildings for which conversion notices were sent before July 1.

The suit seeks a temporary injunction ordering the landlord to withdraw the conversion notices and pay penalties of up to $500 for each violation of the county's condominium law. A hearing is scheduled for June 25.

Montgomery County has lost about 5,000 of its 55,000 rental units to condominiums in the past year and a half, despite the expiration of rent control laws last January and a plethora of local conversion regulations.

Bills passed by the Maryland General Assembly which go into effect in two weeks empower local governments to give themselves or a designated agency the right of first refusal in the purchase of a building. They also require developers to extend tenancies for income-eligible elderly and handicapped persons for three years after a conversion and to pay up to $750 in moving expenses for tenants who do not buy their apartments.

The Montgomery County Council is holding work sessions this month on its own package of condominium bills that would extend the three-year tenancies to life and provide financial assistance to qualifying elderly and handicapped renters.

The owners of the building could not be reached for comment. A spokesman for H. G. Smithy Company, the managers of the building, said he did not know anything about the suit.