Dr. K. C. Kent Lloyd of the University of California, Davis, a co-chairman of the working group that prepared the report, said in a hearing Tuesday that was streamed online that his group made field trips to seven chimpanzee facilities, including laboratories and sanctuaries.

He said the group was asked to consider what living conditions were appropriate for chimpanzees, the species closest to humans and highly intelligent and social. Even if experiments are approved in the future as being necessary for human health and undoable in any other way than using chimps, he said the animals must have “environments that not only allow but promote the full range of natural chimp behavior.”

That means room for social groups, and, Dr. Lloyd added, “No chimp should live alone for an extended period of time.”

The report recommends canceling six of nine current biomedical research projects that involve immunology and infectious agents. The report does not specify the nature of the research, but one of the few areas where some scientists consider chimp use important is in work on hepatitis C because no other animals provide a useful model for research, which involves infecting the chimps with the virus.

In less invasive research on behavior and genetics, 15 projects were approved or conditionally approved to continue and six projects ended.

The report also offers a plan for the independent committee to evaluate future research proposals, based on the guidelines proposed in December 2011 by the Institute of Medicine, which emphasized that human health must be at issue and that there must be no other way to do the research.

Tuesday’s recommendations come in the midst of efforts on several fronts to end experiments on chimpanzees, including a bill to stop experimentation on all great apes, which did not pass in the last Congress, but which proponents hope to reintroduce, and a pending decision by the Fish and Wildlife Service on whether captive chimps should be considered endangered, as wild chimps are.