Intensity Lab
MMI Scale › Level VI
VI

Strong

Strong shaking · Light damage potential

PGA
9.2 – 18 %g
PGV
16 – 31 cm/s
I II III IV V VI VII VIII IX X

Felt by all; many frightened. Some run outdoors. Walking feels unsteady. Damage slight.

Effects

People & Response

  • Felt by everyone; many frightened
  • Many run outdoors
  • Walking feels unsteady
  • Some difficulty standing

Objects & Furnishings

  • Windows and dishes fall and break
  • Books and objects fall from shelves
  • Small bells ring loudly
  • Heavy furniture moved or overturned

Structures & Environment

  • Plaster falls from walls and ceilings
  • Chimneys crack
  • Trees shaken slightly to moderately
  • Slight damage to ordinary buildings
Typical PGA (ShakeMap) 9.2 – 18 %g
Typical PGV (ShakeMap) 16 – 31 cm/s
PGA/PGV ranges are approximate; values overlap between adjacent levels. See Instrumental Intensity for details.

Video Example

MMI VI shaking example video thumbnail
Watch on YouTube ↗
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Descriptions are verbatim from the USGS MMI Scale, based on Wood & Neumann (1931) and Richter (1958). Source: USGS Modified Mercalli Intensity Scale .

Instrumental intensity values and PGA/PGV ranges from USGS ShakeMap V4 Technical Documentation (Worden et al.). Intensity Lab reports MMI derived via the Worden et al. (2012) GMICE, interpolated from USGS ShakeMap. PGA/PGV ranges are approximate; actual values overlap between adjacent levels.