Leonardo,
I think that you should revise your scenario and try to fit into SAP standard flow.
The proper transaction for exposure groups is EHSPP01, where you can define all the people who undergo a particular kind of risk.
Among others, you have to set Analysis on EHSVU11 and then customize your personal Health Surveillance Protocol via EHSVU01: here you can trigger a Protocol from an HR task, if your HR team has implemented Work Areas and Tasks.
etc.
You should have a look at this very good document:
http://scn.sap.com/docs/DOC-41109
from Crhistoph, and I swear it's not only for beginners but a good reference doc.
Kind Regards,
Daniele