Full approval would allow the vaccine to remain on the market as the pandemic fades.It may also make it easier for companies, government agencies, schools and other entities to require vaccination. The University of California and California State University school systems, for instance, have announced that once coronavirus vaccines receive full F.D.A. approval, they will require students, faculty and staff members to be vaccinated. The U.S. military, which has seen many troops decline coronavirus vaccines, has said that it would not make them mandatory as long as they have only emergency authorization.