The Radiological Response and Emergency Management System (RREMS) is a system managed by the Department for Energy Security and Net Zero and used by the Government of the United Kingdom which records and analyses the level of radioactivity across the United Kingdom. A reading is taken from each of the over 200 stations every hour and an alert triggered if radiation levels for specific isotopes rise significantly above normal background radiation levels at one or more stations. RREMS replaced the older Radioactive Incident Monitoring Network (RIMNET) system in September 2022.