The District of Columbia City Council, alarmed by a "sharp increase" in the number of city apartments being converted to condominiums, yesterday passed emergency legislation designed to make it more difficult for some apartment building owners to convert their properties.

The legislation, if signed by the mayor, will make any apartment building or complex ineligible for conversion to condominiums if monthly apartment rents charged there are less than $221 for an efficiency, less than $267 for one-bedroom apartment, less than $314 for two bedrooms, and less than $408 for any larger model.

Under current emergency legislation passed by the Council last March, condominium conversion was forbidden for any apartment complex tha rented its one-bedroom models for less than $247, two-bedroom models for less than $288, and any larger unit for larger $403.

That emergency legislation is to expire June 10. Yesterday's council action, in addition to making it tougher to convert to condominiums, will extend that current expiration date another 90 days.

The increase in condominium conversions is housing stock in the District of Columbia," the council's resolution, adopted yesterday, noted.

According to figures supplied recently by the mayor's office, more than 1,000 rental units have been converted to condominiums this year, compared to 430 for all of last year. Landlords have received permission to convert the apartments of an additional 1,600 tenants but have not yet done so.

Mayor Walter Washington earlier this month proposed legislation that would raise the rent levels determining eligibility for condominium conversion even higher. An apartment building or complex would be ineligible if a two-bedroom rented for under $375, for example. The mayor's proposal also would place restrictions on other types of conversions.

City Council housing committee chairman Nadien Winter (D-Ward 6) said her committee has reviewed the mayor's proposal at the request of City Council Chairman Sterling Tucker and has asked for additional information. The committee currently is considering permanent legislation to regulate condominium conversion.

John T. O'Neill, of the Apartment and Office Building Association, said yesterday he expects affected landlords will challenge the Council's latest action which he called "sad news for the city."

"I think that it's incredible that they (the Council) simply ignored the cause (of the conversions) and are trying to prohibit people from properties that aren't winners economically any more," O'Neill said. "If they want to stop condo conversion, they ought to figure out that unless a landlord is making a resonable return on his investment, then he's going to continue to sell out."

O'Neill added, "Next month it'll be another change as we get into the heat of political races . . . Eventually, this kind of one-upsmanship that goes on monthly in the City Council is going to have to be challenged."

O'Neill also contended that the use of federal rent subsidy program information by the council to help it establish fair market rents for condominium conversion results in "phony rent levels" because it includes suburban jurisdictions rents in addition to those of the District of Columbia.

Evelyn Onwuachi, chairperson of the Citywide Housing Coalition, had reserved praise for the council action.

"It's an excellent piece of legislation, but it's stopgap. It doesn't make anything (more) available for people.

It maintains the existing stock,' Onwuachi said.