Approximately Time in Hours for Early Federal Technical Response Activities after a Nuclear Detonation - Illustration Source of graphic: Exploring Medical and Public Health Preparedness for a Nuclear Incident: Proceedings of a Workshop (2019), (NASEM, Figure 2-11, page 33, presented at the meeting by John Crapo.) This graphic shows a partial list of agencies from the US government that could respond with technical assistance to a large mass casualty radiation incident like a nuclear detonation. For a full list of agencies and their responsibilities after a nuclear detonation see the Nuclear/Radiologic Incident Annex to the Response and Recovery Federal Interagency Operational Plans, October 2016 - Final. See Appendix 1, pages 1-8. Department of Energy assets begin participating at different times, as shown on the graphic above. See description of the roles of the various DOE agencies shown in graphic. Department of Defense groups include but are not limited to the following teams Civil Support Team (CST) Homeland Response Force (HRF) which are mostly National Guard groups. Advisory Team (A-Team) is comprised of personnel from various US government agencies. The Federal Radiological Monitoring and Assessment Center (FRMAC) is an asset from DHS. Environmental Protection Agency (EPA) is an independent agency of the US government.