A casualty is the most critical situation that may face a documentary center. The Second World War, the Balkan conflict and the collapse of the Historical Archive of Cologne are well known for a long list of desolation that has decimated the precious legacy of our ancestors examples. Its causes are varied, but in any case, generate violent alteration processes in a few hours, are capable of completely destroying documents, deposits and entire files. Not all disasters are inevitable. Most could have been controlled through processes of risk assessment and remediation planning known as casualty or disaster management. Based on methodologies used in civil protection, encompassing prevention techniques and conservation which can prevent fire, flood or any other destructive phenomenon. They also allow work to establish protocols and gather the necessary resources to act properly in the protection and rescue of documentation. This manual is a practical guide. Through seven consecutive steps supported by summary tables and custom forms, facilitates writing disaster plans tailored to different file types, regardless of their size or resources.