Radiotherapy - ringing bell at end of treatment

I know this is silly given the magnitude of cancer and it’s treatment but at my radiotherapy session today a patient finished her treatment and all the staff came out to cheer as she rang the bell. It was really emotional for all but I recoiled in horror as it’s something I would hate to do. 

Is it compulsory? Do the staff ask beforehand? It’s been worrying me all day. I’m now dreading my final session. Again apologies for being petty.