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Rossi-Forrel Scale of Earthquake Intensities (Original) PDF Print
Friday, 09 May 2008 19:35
Intensity Scale Description

Microseismic shock. Recorded by a single seismograph of by seismographs of the same model, but not by several seismographs of different kinds: the shock felt by an experienced observer.


Extremely feeble shock. Recorded by several seismographs of different kinds; felt by a small number of persons at rest.


Very feeble shock. Felt by several persons at rest; strong enough for the duration to be appreciable.


Feeble shock. Felt by person in motion; disturbance of movable objects, doors windows, cracking of ceilings.


Shock of moderate intensity. Felt generally by everyone; disturbance of furniture, beds, etc., ringing of some bells.


Fairly strong shock. General awakening of those asleep; general ringing of bells; oscillation of chandeliers; stopping of clocks; visible agitation of trees and shrubs; some startled persons leaving their dwellings.


Strong shock. Overthrow of movable objects; fall of plaster; ringing of church bells; general panic, without damage to buildings.


Very strong shock. Fall of chimney; crack in the walls of buildings.


Extremely strong shock. Partial of total destruction of some buildings.


Shock of extreme intensity. Great disaster; ruins; disturbance of the strata, fissures in the ground, rock falls from mountains.