Two people were hospitalized after what officials called a minor explosion in a lab at the UConn Cell Genome Sciences Building in Farmington Tuesday.
Three other people who were in the lab are being checked out and about 40 people were evacuated from the building.
The building is part of the University of Connecticut Health Center.
Staff members were allowed back in the building to gather their belongings around 4:45 p.m.
The building, dedicated earlier this year, houses the UConn Stem Cell Core Lab, the R.D. Berlin Center for Cell Analysis and Modeling, the Department of Genetics and Developmental Biology, and the Technology Incubation Program, which is assisting in the commercialization of UConn research and providing incubator space for start-up businesses.
The Health Center hoped to reopen the building by Wednesday.