Dr. Marr leads the Applied Interdisciplinary Research in Air Laboratory, which studies pollutants in indoor and outdoor air. She is especially interested in emerging or non-traditional aerosols such as microorganisms and engineered nanomaterials and how they are transformed in the environment. Prior to the pandemic, she was one of a small number of researchers who studied viruses in the air. She is a Co-Principal Investigator of COMPASS and Co-lead of the Persist Thrust. She is collaborating with other COMPASS team members to develop predictive models of virus inactivation in the environment.