Data and Methods
FEMA has recently published a series of tutorial videos highlighting the main features of the National Risk Index and explains the methodologies behind our interpretation of risk data. Click here to view the list of videos.
Selecting Data
After completing a thorough review and evaluation, the National Risk Index development team and working groups collaborated to select datasets and indices from reputable sources across the United States.
All data supporting the National Risk Index risk components were required to be nationwide in scope and able to be measured at the county and Census tract levels. Hazard data sources were also required to have location and time information.
Collecting Data
Data supporting the National Risk Index were collected from both publicly accessible resources and organizational connections. Data were last collected between 6/1/2021 - 12/15/2022.
Processing Data
The National Risk Index is supported by aggregated and normalized data. Individual datasets were subject to varying analyses depending on the data format and structure. Some datasets collected were already normalized and were more easily incorporated into the Index.
For more detail about data selection, collection and processing methods, visit each Risk Index component's or risk factor's page, or see the National Risk Index Technical Documentation.