What is MMI?

MMI stands for Modified Mercalli Intensity and relates to the amount of ground shaking that was caused by an earthquake. The effect of an earthquake on the Earth's surface is called the intensity. The intensity scale consists of a series of certain key responses such as people awakening, movement of furniture, damage to chimneys, and finally - total destruction.

What is Exposure?

Exposure is defined as “the people, property, systems, or other elements present in hazard zones that are thereby subject to potential losses” (UNISDR 2009). Understanding vulnerability and exposure are fundamental to our understanding of risk.

Why is MMI 6 the threshold for Exposure in this Dashboard?

MMI 6 is a conservative estimate of where buildings in the USA may potentially become damaged due to ground shaking for initial response and planning purposes only. Please refer to the Hazus Results App in this journal for authoritative damage estimates.

Earthquake Population Impacts Dashboard

Use the tabs in the Hazus Results Viewer to toggle between Hazus Results for recent earthquake events.

The Hazus Earthquake Model provides loss estimates of damage and loss to buildings, essential facilities, transportation and utility lifelines and population based on scenario or probabilistic earthquakes. The model addresses debris generation, fire-following, casualties and shelter requirements.

The authoritative Hazus Run of Record for each major earthquake event is performed by hazard modeling specialists at FEMA in conjunction with the USGS National Earthquake Information Center.

Hazus Results Viewer

A collection of public and authoritative Web Applications within the Earthquake Incident Journal.