The Earthquake Zones
Seismic risk varies dramatically by location within the US:
Pacific Coast high risk: California (the San Andreas Fault system and many related faults), Western Washington and Oregon (the Cascadia Subduction Zone), and Alaska (among the world's most seismically active areas). These areas face both frequent moderate earthquakes and the potential for infrequent catastrophic events.
Interior seismic zones: The New Madrid Seismic Zone (Missouri, Tennessee, Arkansas, Illinois) last produced a series of catastrophic earthquakes in 1811-1812. The region is less built to seismic codes than the West Coast and would experience severe damage in a large event.
Pacific Northwest Cascadia scenario: This deserves specific attention because it's dramatically different from a typical California earthquake in scale. The Cascadia Subduction Zone can produce a magnitude 9.0 event affecting hundreds of miles of coastline. The Oregon Office of Emergency Management has been explicit: a full-fault Cascadia rupture will produce a tsunami affecting coastal areas, destroy infrastructure throughout the Pacific Northwest coast, and require 2+ weeks of community self-sufficiency before significant outside help arrives.
Pre-Earthquake Home Preparation
Structural Assessment
Year built and foundation type matter: Unreinforced masonry buildings (common pre-1940s construction in the West), older concrete buildings without rebar, and wood-frame houses without proper foundation connections are most vulnerable. If your home is pre-1980 construction in a high-risk seismic area, a structural engineer's seismic assessment is worth the $500-1,500 cost.
Soft story buildings: Multi-story buildings with open ground floors (garages, retail spaces) are particularly vulnerable to pancake collapse. If you live in a soft-story building in a high-seismic area, know your building's risk category.
Non-Structural Hazard Mitigation
Most earthquake deaths are from falling and falling objects — not structural collapse. Non-structural mitigation:
Water heater: Strap to wall with approved seismic straps ($20-40). Unstrapped water heaters tip and rupture gas lines.
Large furniture: Bookcases, cabinets, dressers — anchor to wall studs. Furniture falling is a leading cause of earthquake injury.
Heavy items above head height: Move heavy items off upper shelves. Overhead items fall on sleeping people during nighttime earthquakes.
Latching cabinet hardware: Magnetic child-safety latches or proper latching hardware prevent cabinet contents from spilling.
Flexible gas connectors: Standard rigid gas connectors can rupture during shaking; flexible connectors allow movement. Verify your water heater and gas range have flexible connectors.
The 72-Hour to 2-Week Supply
Earthquakes damage water mains, gas lines, and roads. Immediate supply disruption is predictable.
Water is the first priority: Broken water mains mean no tap water for days to weeks. A 2-week supply per person is the Cascadia recommendation; minimum 72 hours for any high-seismic area.
Food: 2 weeks no-cook or minimal-cook food.
Medical: Prescription medications, first aid — you will not be able to get to a pharmacy for days.
Documents and financial: See documents-to-waterproof.mdx.
During the Shaking
Drop, Cover, Hold On — the evidence-based response:
- Drop to hands and knees (reduces fall injury; lets you move if needed)
- Cover — get under a sturdy table or desk if available; if not, cover head and neck with arms
- Hold On — if under a table, hold on to it and move with it; protect your head and neck
- Stay in place until shaking stops
If there's no nearby table: Get against an interior wall away from windows, cover your head and neck with your arms.
In bed: If awakened by an earthquake, stay in bed and cover your head with a pillow. Rolling out of bed onto glass or debris on the floor while disoriented is a significant injury risk.
In a kitchen: Move away from the stove and move toward a table or corner. Falling cabinets are the main hazard.
Outdoors: Move away from buildings, power lines, trees. Many earthquake deaths occur from building facade pieces falling on people who ran outside.
After the Shaking Stops
Immediate assessment:
- Check yourself for injury. Adrenaline can mask pain.
- Check others in your household.
- Smell for gas. Do not turn on any lights if you suspect a gas leak — exit immediately and leave doors open behind you. Notify the gas company.
- Check for structural damage before staying in the building. Visible cracks in foundation or load-bearing walls, settled or shifted structure, visible damage to roof — these may indicate the building is unsafe to occupy.
After a major earthquake, expect:
- Power outage for hours to days (weeks after major event)
- Water outage for days to weeks
- Aftershocks — typically smaller than the main event but can be significant
- Road and bridge closures
- Cell network congestion (text messages will get through; voice calls may not)
Aftershock preparation: After the main event, the risk of another significant shake is elevated. Re-apply Drop, Cover, Hold On for every significant aftershock. Major aftershocks can cause buildings already weakened by the main event to fail.
The Cascadia Specific Plan
If you live in the Pacific Northwest coast region:
Know your tsunami zone. Coastal communities have clearly delineated tsunami inundation zones. A Cascadia event will produce coastal waves within 15-30 minutes of the main shaking. If you're in the tsunami zone and you feel a long, strong earthquake — start moving inland on foot immediately. Don't wait for an official warning.
The vertical evacuation question: Some areas in the inundation zone don't have high ground within walking distance. Some communities have built vertical evacuation structures (tall, tsunami-resistant towers). Know if your community has one and where it is.
2 weeks minimum: Plan for 2 weeks of self-sufficiency, not 72 hours. Roads into coastal communities will be cut by landslides, bridge damage, and flooding. Helicopter airlift is the primary resupply mechanism; the capacity for this is limited.
Out-of-region contact: Have a contact person in another region who can receive information from your household and relay it to concerned family. Local communication infrastructure will be severely disrupted.
Sources
Frequently Asked Questions
Does the Triangle of Life technique actually improve earthquake survival?
No. The 'Triangle of Life' (shelter beside furniture rather than under it) contradicts the advice of FEMA, WHO, and every major seismic safety organization. It was promoted by Doug Copp, a non-credentialed individual whose claims have been systematically debunked. The evidence-based recommendation is Drop, Cover, Hold On — get under a sturdy table or desk, cover your head and neck. For more on this, see FEMA's response to the Triangle of Life claim.
How long should I be prepared to be self-sufficient after a major earthquake?
FEMA's recommendation for earthquake-prone areas is a minimum of 72 hours. For areas near the Cascadia Subduction Zone (Oregon, Washington, Northern California coast), the Oregon OEMS is explicit: 2 weeks of self-sufficiency is the recommended planning duration. A Cascadia full-fault rupture would cut off coastal communities for weeks as roads, bridges, and infrastructure are damaged.
Should I run outside during an earthquake?
No. Most earthquake injuries occur from falling objects inside buildings, but the transition between inside and outside (passing under an overhang or awning, running near walls that may fall) is dangerous. Stay inside until the shaking stops; then assess whether the building is safe before moving. If outside, move away from buildings, power lines, and trees.