An activity monitoring health smart home (HIS type) based upon an infrared sensor network and the related data fusion was deployed in intermediate and long term geriatric wards. Frail elderly people in those facilities are the closest substitute to home-dwellers, yet the staff provides the standard for activity monitoring. We could show that : 1. HIS is little intrusive and readily accepted. 2. We may model the capabilities of HIS to trigger an alarm and compare it to other devices measuring activity in specific frail populations. 3. We proved our model on the clinical case of a falling Lewy's bodies disease patient. 4. ISOFDIS 14971 norm on risk management may apply to HIS. 5. Returns may be expected from the first implementation year if an HI Sis deployed at the home a frail elderly lady with cardiovascular condition. Therefore, proposing a commercial service using HIS is medically, socially and economically relevant.
