The Prince George's County Council voted yesterday to curb county transactions with companies and banks that do business with South Africa by prohibiting purchases from those firms and deposits of county funds in those banks.

The council also adopted two resolutions that call for a review of the county's investment practices with South Africa-related companies.

The unanimous votes came after months of deliberation and a series of alterations to the legislation, which was introduced by council member James M. Herl.

One of the key amendments, made in committee, removed provisions in each of the four measures passed yesterday that would have allowed firms that have ties to South Africa to trade with the county if the firms adhered to the Sullivan Principles, guidelines under which firms hire, pay and assign workers without discriminating. Herl called those guidelines "archaic."

The council votes follow a national campaign by activists opposed to South Africa's system of racial segregation to cut U.S. ties to South Africa. The District of Columbia enacted a law this year that prohibits the city from investing funds in banks and other institutions that do business with South Africa. In March, Montgomery County Executive Charles Gilchrist instructed the county's insurance company not to put county pension funds in South African-related investments.

Dorothy Thomas of the Washington Office on Africa said yesterday that the exclusion of exemptions for companies adhering to the Sullivan Principles makes the Prince George's and District laws stricter than much of the local legislation that has been passed in the country.

County officials would not say how much the purchasing curb would cost, but they said they could accept whatever loss is incurred. The county has no funds deposited in banks that have South African ties, officials said.

During council work sessions on the issue, county officials had said that prohibiting investments in South Africa-related firms could cost the county up to $500,000 a year.

Only council member Frank Casula, who eventually voted in favor of the legislation, expressed reservations about the measures. "Instead of doing something good, we might be doing an injustice to the people" of South Africa, he said in a reference to arguments that U.S. companies operating in South Africa provide jobs for black workers there.

In other action, the council agreed on a 5-to-4 vote to establish a $50 fee for ambulance service. Fire Chief James Estepp said the fee will raise about $200,000 a year and allow the county to double the number of intensive care ambulances, to 12.

"Nearly 200 citizens in our county are dying needlessly each year who might have been saved by paramedics," he told the council. Voting in favor of the bill were Herl, JoAnn T. Bell, Richard Castaldi, Hilda Pemberton and Floyd E. Wilson. Voting against were William B. Amonett, Casula, Anthony Cicora and Sue V. Mills.

About 30 people testified on the bill. Estepp's contention was supported by an array of doctors, fire personnel and others.

But Betterment for United Seniors, a lobbying group, and others argued that the fee will be a burden to people on fixed incomes.

"I don't like it because I already pay taxes, and those taxes I assume are supposed to go to my health and welfare," said group member Rachel Pemberton.

"It's a matter of priorities," council member Sue V. Mills said. "We had $11 million to buy back bad debts from the county hospital system . The executive found $9 million just like that for the school system.

"We manage to pay for what we consider to be our top priority, and we've never looked at paramedic units in that light."