You can start a scan of an existing sandbox to measure the results against policy rules.
From the list of sandboxes, click the required sandbox name to go to the overview page.
Click Start a Scan and, then, select the scan type you want to run.
Follow the same procedures for running formal, policy scans.
To review which sandbox scans are still running and which have finished, go to the left navigation menu of the application and under Sandbox Scans, click In Progress or Completed.