A Body Area Network (BAN), which consists of radio-enabled wearable or implantable sensor nodes, is a technology that enables pervasive monitoring & delivery of health-related information & services. While this technology can be integrated with existing IT infrastructure to extend the coverage of healthcare service providers to the user location, it can also facilitate independent living for people that require constant health monitoring. Therefore, it can transform and significantly enhance the patient health-care experience. Considering the high quality of service required for the operation of such networks, interference among multiple BANs and also from other existing wireless systems (Wi-Fi, UWB, Bluetooth, etc) could cause a serious problem on the reliability of their operation. NIST researchers are developing tools that can help to study the interference on wearable and implantable wireless medical sensors.