The sixth SEGmente volume serves as a guideline and practical manual for responding to incidents involving hazardous materials, which often result in a mass casualty situation. The volume outlines the spatial organization and the necessary distances between contaminated and decontaminated areas. It presents the required operational tactics as well as the recommended protective equipment. In the third edition, the medical management of mass casualty situations involving CBRN-contaminated victims has been further developed and refined. Checklists and information regarding the DEKON-V module and SEG-VERKON provide a practical guide for optimal preclinical care while ensuring appropriate self-protection for responders and comprehensive protection against contamination spread.