The Committee on the Present Danger, a hard-line group that has criticized the emerging strategic arms limitation treaty (SALT), released a public opinion poll yesterday challenging the impression that Americans overwhelmingly support a new SALT agreement.

The committee commissioned the poll to test the conclusions of other polls that found large majorities favoring nuclear arms control agreements with the Soviet Union. By asking more detailed questions, the committee said yesterday, its poll found that the public is woefully ignorant about SALT and much more skeptical than previously reported.

Polling experts queried by The Washington Post yesterday said the committee's poll departed from normal polling practices by asking questions that might appear loaded and by asking extremely complicated questions that recipients in a telephone survey would be unlikely to comprehend.

The question of the true level of popular support for SALT is a significant one because the Carter administration has repeatedly invoked the findings of other polls showing overwhelming support for SALT as a reason why senators should support it.

Spokesmen for the committee criticized those polls yesterday as too vague. They specifically criticized a headline in The Washington Post last month over a story reporting one of the polls. The headline said: "81 Percent in U.S. Back New SALT in Poll."

The poll was one conducted by NBC and the Associated Press which asked: "Do you favor or oppose an agreement between the United States and Russia which would limit nuclear weapons?" Eighty-one percent of those queried said yes. A committee spokesman noted that the question did not ask about the actual SALT II accord being negotiated.

The committee's own poll -- designed by William Connell, a political consultant and film producer who once worked for the late Sen. Hubert H. Humphrey (D-Minn.) as a senior aide -- put a more complex question to its sample of 1,211 adults. (The poll was conducted by George Fine Research, Inc., a respected New York firm that has done poll interviewing for The Washington Post in the past, among others.)

The question was: "The United States is now negotiating a strategic arms agreement with the Soviet Union in what is known as SALT II. Which one of the following statements is closest to your opinion on these negotiations:

1. I strongly support SALT II.

2. SALT II is somewhat disappointing, but on balance, I would have to support it.

3. I would like to see more protection for the United States before I would be ready to support SALT II.

4. I strongly oppose the SALT II arms agreement with the Russians.

5. I don't know enough about the SALT II treaty to have an opinion yet."

Only 8.3 percent gave strong support to SALT II in this poll, while 8.6 percent said they were strongly opposed. Most respondents -- 41.7 percent -- picked the "more protection for the United States" answer, while 29.6 percent had no opinion.

Queried about this question yesterday, Paul B. Sheatsley, senior survey director of the University of Chicago's National Opinion Research Center, said it was "probably not a balanced question."

"Everybody wants to see more protection for the United States," Sheatsley said, adding that a fairer poll would have offered a range of answers, all in neutral language.

The Committee on the Present Danger also asked detailed questions based on the contents of SALT II to see if people knew what was in it (two-thirds or more of them apparently did not) and to determine how attitudes changed if certain information was provided. Sheatsley and other polling experts said these questions were argumentatively drafted and too difficult for the general public to understand.

Sheatsley, who has written widely on polling techniques, said the simpler questions asked by the big polling organizations "set the atmosphere" and "show that in general public opinion is favorable toward negotiating a new agreement."

He expressed the opinion that citizens who have no expert knowledge of SALT could not be expected to give considered answers to detailed questions about it.