Extreme: Alarm may approach panic, major structural damage, widespread destruction.
Light: Generally noticed indoors, moderate vibration or jolt, light sleepers may be awakened.
Moderate: Felt outdoors and indoors, small objects may be shifted, some glassware may break.
Unnoticeable: Not felt at all.
Severe: Difficulty standing, significant damage to fragile or unsecured objects.
Unnoticeable: Felt indoors as a light vibration, no effect outdoors.
Strong: Felt by all, furniture and appliances may move, some non-structural building damage.
No data or unclassified intensity.
Weak: Felt indoors as a light vibration, hanging objects may swing slightly.
Unnoticeable: Barely sensed by a very few people.