The information provided by CHEMM enables first responders, first receivers, other healthcare providers, and planners to plan for, respond to, recover from, and mitigate the effects of mass-casualty incidents involving chemicals. CHEMM was produced by the U.S. Department of Health and Human Services, the Office of the Assistant Secretary for Preparedness and Response, the Office of Planning and Emergency Operations, in cooperation with the National Library of Medicine, Division of Specialized Information Services, and many medical, emergency response, toxicology, and other types of experts. It’s a comprehensive, user-friendly, web-based resource that is also downloadable, so that it can be available during an event, if the internet is not accessible.