MOSCOW, DEC. 10 -- An independent seminar on human rights, seen as a test of the Kremlin's tolerance for open discussion, opened in a private apartment here today after authorities suddenly closed down a rented public meeting place for "disinfection."

Representatives of human rights monitoring groups from Czechoslovakia, the United States and Sweden attended the seminar's opening, but a number of international figures from West Germany, Poland and elsewhere were refused visas by Soviet authorities. Several Soviet participants also have been stopped, or strongly discouraged, from attending, organizers said.

Lev Timofeyev, head of the Press Club Glasnost, which organized the seminar, said the series of obstacles should not be regarded as "coincidental."

"It shows the serious inability of Soviet organs to carry on a dialogue with independent public opinion," said Timofeyev, a former political prisoner and coordinator of the four-day seminar. But overall, he said, he saw the official response as a sign that authorities want to avoid a "direct scandal" over the seminar, which opened on the United Nations' International Human Rights Day and the last day of Soviet leader Mikhail Gorbachev's visit to the United States.

At a press conference opening the seminar, Sergei Kovalyov, another organizer and former political prisoner, suggested that authorities were trying to discourage the event in Gorbachev's absence, perhaps to embarrass him. But most observers here saw the response to the seminar as part of a developing trend to curb any challenge to government control under the conditions of glasnost, or openness.

The opening session of the rights seminar had been scheduled to take place in a meeting hall in the Kirov region of northern Moscow, rented in advance with a deposit of 300 rubles -- about $450 at the official exchange rate. But when participants arrived this afternoon, along with a number of western journalists, they found a padlock on the door and a sign saying the hall was closed for a "sanitation day."

"The official reason is the hall needed an urgent disinfection," said Sergei Petrov, spokesman for the seminar. He said inquiries would be made later about retrieving the deposit.

The group moved to an apartment in central Moscow, followed by unmarked police cars and surveillance vans that parked ostentatiously outside the entrance to the apartment. Timofeyev said the closing of the public hall presented the group with an "unexpected, complicated situation, but it has not affected our intentions."

Once officially ignored, world opinion about human rights in the Soviet Union now seems to be officially recognized here. Recently, an official committee was created to raise awareness of human rights problems. It is to be headed by a prominent newspaper commentator, Fyodor Burlatsky.

The unofficial seminar is one of the byproducts of Gorbachev's policy of "openness" and his campaign to broaden the public's participation in political and economic decisions. Over the last year, Gorbachev's policies have led to the freeing of almost 200 political prisoners, the opening of debate in the official press and the establishment of scores of unofficial groups and journals.

But since the late summer, the police and the KGB security forces have adopted stricter tactics limiting public demonstrations and curbing dissident activity. Two days ago, 20 members of the seminar's organizing committee were visited at their apartments and handed notices, signed by assistant local prosecutors, warning them that the seminar was illegal.

A week ago, the organizers were told by the Moscow executive council that they would not be given an official public meeting place, but they were not forbidden from meeting.

The plans for the seminar, announced in September by the Press Club Glasnost, call for sessions on such topics as the rights of the disabled, freedom of speech and religion, and international trust and disarmament. The sessions are to be held over the next three days in various Moscow apartments, with a concluding meeting scheduled for another public hall.

One of the key speakers at the seminar, Jan Urban, is a member of the Czechoslovak dissident group Charter 77. He arrived yesterday after a companion, Venek Silhan, was detained by police at the Prague airport.

Urban said the Moscow seminar was viewed as "a very important event" in Czechoslovakia, a test to see "if it will be possible for unofficial movements like Solidarity {in Poland} and Charter 77 to come and discuss freely." The Soviet Union announced a year ago that it would hold an official human rights conference in Moscow in 1988, but western governments have insisted that certain rights be guaranteed before they agree to participate.

"If this seminar is not possible because of repression by the KGB, then it shows Moscow is not prepared and these words are just words," said Urban.

Although Soviet visa authorities denied entry to Petra Kelly, a leader of the West German Greens party, to attend the seminar, several American participants were allowed into the country after listing the unofficial Glasnost club as their sponsor.

Among those attending from the United States are Martha Henderson, of Humanitas, a California rights group, Jan Kovarich of Washington's International Parliamentary Group for Human Rights in the Soviet Union and representatives of U.S. Jewish and Ukrainian groups.

Physicist and Nobel Peace Prize winner Andrei Sakharov, viewed as the father of the Soviet human rights movement, will not attend the seminar, according to Kovalyov.

"He said he will follow it with interest and read its reports. He said he supports it," said Kovalyov. "But he said he intuitively feels he should not take part."