The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From NCPTT National Park Service:
Based on the original slide-chart Emergency Response & Salvage Wheel, a well-respected cultural heritage protection tool, the Emergency Response and Salvage app outlines critical stages of disaster response, such as stabilizing the environment and assessing damage. It also provides practical salvage tips for nine types of collections: photographs, books and documents, paintings, electronic records, textiles, furniture, ceramics/stone/metal, organic materials, and natural history specimens. This app will help users protect precious collections and significant records, access reliable information instantly, and save damaged objects.