By: Ruthie Helms
Earthquakes have been making headlines and shaking things up – particularly in regions across the U.S. that are not prone to them. Just last year, New York City experienced a 4.8-magnitude earthquake that rocked residents and proposed the risk of structural damage.
While the earthquake in New York City did not cause wide-scale infrastructure damage, it did raise questions on building safety and whether some regions across the U.S. are prepared for an earthquake to strike.
Older Buildings are at Risk
We can’t prevent an earthquake, but what we can do is adopt and enforce modern building codes to limit destruction. Millions of old structures across the U.S. contained unreinforced masonry and other vulnerable components, increasing the risk of their collapse.
Unless a building has been significantly renovated, altered, or changed in use (triggering the International Building Code or the International Existing Building Code), it is generally only required to meet the codes that were in effect when it was originally built. As a result, many buildings that have stood for decades do not meet current seismic standards.
In the U.S., seismic codes began to gain traction in different regions at different times:
Buildings constructed before these periods are likely not seismically safe.
IEBC and Seismic Standards
The International Existing Building Code (IEBC) governs how existing buildings can be altered, repaired, expanded, or adapted for new uses. Since 2000, many states and municipalities have adopted the IEBC and other International Codes published by the International Code Council (ICC), which unified three regional code organizations (BOCA, SBCCI, and ICBO).
If an evaluation finds that a building is seismically deficient, retrofitting should be carried out using ASCE/SEI 41-06standards, which are referenced in the IEBC. For further guidance, FEMA 356 and FEMA 547 provide extensive information on retrofit strategies and techniques.
Retrofitting can be critical for seismically vulnerable buildings for safety, economics and community resilience. It leads to fewer injuries, lower economic losses and faster recovery time for individuals, businesses and the areas as a whole.
The Solution? Building Codes.
There is no more powerful tool for earthquake risk reduction than enforcing up-to-date building codes. In addition to codes, communities must also:
By strengthening the built environment, areas across the U.S. can improve their ability to survive, recover and thrive after an earthquake.
