One of the most frightening and
destructive phenomena of nature is a severe earthquake and its terrible
strike suddenly, violently, and without warning at any time of the day
or night. If an earthquake occurs in a populated area, it may cause many
deaths and injuries and extensive property damage.
Although there are no guarantees of safety during an earthquake,
identifying potential hazards ahead of time and advance planning can
save lives and significantly reduce injuries and property damage.
Modified Mercalli Scale & The Richter Scale
The Modified Mercalli Scale
Level Of Damage
The Richter Scale
||Instrumental to Moderate
||Damage negligible. Small, unstable objects displaced or upset;
some dishes and glassware broken.
||4.4 - 4.8
||Damage slight. Windows, dishes, glassware broken. Furniture
moved or overturned. Weak plaster and masonry cracked.
||4.9 - 5.4
||Damage slight-moderate in well-built structures; considerable in
poorly-built structures. Furniture and weak chimneys broken. Masonry
damaged. Loose bricks, tiles, plaster, and stones will fall.
||5.5 - 6.1
||Structure damage considerable, particularly to poorly built
structures. Chimneys, monuments, towers, elevated tanks may fail.
Frame houses moved. Trees damaged. Cracks in wet ground and steep
||6.2 - 6.5
||Structural damage severe; some will collapse. General damage to
foundations. Serious damage to reservoirs. Underground pipes broken.
Conspicuous cracks in ground; liquefaction.
||6.6 - 6.9
||Most masonry and frame structures/foundations destroyed. Some
well-built wooden structures and bridges destroyed. Serious damage
to dams, dikes, embankments. Sand and mud shifting on beaches and
||7.0 - 7.3
||Few or no masonry structures remain standing. Bridges destroyed.
Broad fissures in ground. Underground pipelines completely out of
service. Rails bent. Widespread earth slumps and landslides.
||7.4 - 8.1
||Damage nearly total. Large rock masses displaces. Lines of sight
and level distorted.
Types of Hazards
Tornado Safety Procedures
Flood Safety Procedures
Wildfire Safety Procedures
Terrorism Safety Procedures
Managing Stress After a Disaster
Children and Disasters
Stress as a First Responder
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