European Macroseismic Scale

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The European Macroseismic Scale (EMS) is the basis for evaluation of seismic intensity in European countries. Most recently updated in 1998, the scale is referred to as EMS 98.

The history of the EMS has began in 1988 when the European Seismological Commission (ESC) decided to review and update the Medvedev-Sponheuer-Karnik scale (MSK-64), which was used in its basic form in Europe for almost a quarter of a century. After more than five years of intensive research and development and a three-year testing period, the new scale was born. In 1996 the XXV General Assembly of the ESC in Reykjavik passed a resolution recommending the adoption of the new scale by the member countries of the European Seismological Commission.

Unlike the earthquake magnitude scales, which express the seismic energy released by an earthquake, EMS 98 intensity denotes how strongly an earthquake affects a specific place. The European Macroseismic Scale has 12 divisions, as follows:

1. Not felt	Not felt, even under the most favorable circumstances.
2. Scarcely felt	Vibration is felt only by individual people at rest in houses, especially on upper floors of buildings.
3. Weak	The vibration is weak and is felt indoors by a few people. People at rest feel a swaying or light trembling.
4. Largely observed	The earthquake is felt indoors by many people, outdoors by very few. A few people are awakened. The level of vibration is not frightening. Windows, doors and dishes rattle. Hanging objects swing.
5. Strong	The earthquake is felt indoors by most, outdoors by few. Many sleeping people awake. A few run outdoors. Buildings tremble throughout. Hanging objects swing considerably. China and glasses clatter together. The vibration is strong. Topheavy objects topple over. Doors and windows swing open or shut.
6. Slightly damaging	Felt by most indoors and by many outdoors. Many people in buildings are frightened and run outdoors. Small objects fall. Slight damage to many ordinary buildings; for example, fine cracks in plaster and small pieces of plaster fall.
7. Damaging	Most people are frightened and run outdoors. Furniture is shifted and objects fall from shelves in large numbers. Many ordinary buildings suffer moderate damage: small cracks in walls; partial collapse of chimneys.
8. Heavily damaging	Furniture may be overturned. Many ordinary buildings suffer damage: chimneys fall; large cracks appear in walls and a few buildings may partially collapse.
9. Destructive	Monuments and columns fall or are twisted. Many ordinary buildings partially collapse and a few collapse completely.
10. Very destructive	Many ordinary buildings collapse.
11. Devastating	Most ordinary buildings collapse.
12. Completely devastating	Practically all structures above and below ground are heavily damaged or destroyed.

The European Macroseismic Scale is the first intensity scale designed to encourage co-operation between engineers and seismologists, rather than being for use by seismologists alone. It comes with a detailed manual, which includes guidelines, illustrations, and application examples.