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Seismic Risk Surveys

San Francisco, CA

IVI conducts seismic risk evaluations to provide an assessment of a property's seismic risk using the methodology developed under the probable maximum loss (PML) approach.

The PML value is not intended to be a guarantee of how buildings will withstand a seismic event; rather, it is a statistical analysis that is intended to suggest how the property will be impacted under a given scenario.

PML values are provided as a mean recurrence interval or a probability of occurrences. The mean recurrence interval is the average period of time, in years, between the occurrences of earthquakes that produce effects of the same, or greater, severity. The probability of exceedance (e.g., 10% in 50 years) is a statistical representation of the chance that earthquake effects exceeding a given severity will be experienced at the site within a specified number of years.

Our PML reports are pragmatic in knowing that technical judgment is required to obtain the PML result. Every building is unique, and the methodology used does not lend itself to a slide rule or calculator approach.

Click to download a PDF of IVI's Seismic Map Zones
Seismic Zone Mape