As Eddy said generally you don't.
If you encounter a virus you should select 'Repair' as your first option and 'Move to chest' as your second option if that doesn't work, always do the thing that will do least harm to your system until you confirm the detection.
If however, you have been using auto send to chest without manual intervention (silent mode), then it may be possible that the file you sent to the chest could be a file that may be repairable. I'm not sure if this can be don within the chest or if you have to move it to another folder (or restore) in order to attempt repair.