Urban and suburban areas, wooded areas, or other terrain with numerous closely spaced obstructions having the size of single-family dwellings or larger. Use of this exposure category shall be limited to those areas for which terrain representative of exposure B prevails in the upwind direction for a distance of at least 1,500 feet (460 m) or 10 times the height of the building or structure, whichever is greater.
Open Terrain with scattered obstructions having heights generally less than 30 feet (9.1 m). This category includes flat open country and grasslands.
Flat, unobstructed areas exposed to wind flowing over water for a distance of at least 1 mile (1.61 km). This exposure shall apply only to those building and other structures exposed to the wind coming from over the water. Exposure D extends inland from the shoreline a distance of 1,500 feet (460 m) or 10 times the height of the building or structure, whichever is greater.
Buildings and other structures that represent a low hazard to human life in the event of failure including, but not limited to:
* Agricultural facilities
* Certain temporary facilities
* Minor storage facilities
All buildings and other structure except those listed in Categories 1, 3, and 4.
Buildings and other structures that represent a substantial hazard to human life in the event of failure including, but not limited to:
* Buildings and other structures where more than 300 people congregate
in one area
* Buildings and other structures with elementary school, secondary school, or day-care facilities with capacity greater than 250
* Buildings and other structures with a capacity than 500 for colleges or adult education facilities
* Healthcare facilities with a capacity of 50 or more resident patients but not having surgery or emergency treatment facilities
* Jails and detention facilities
* Power generating stations and other public utility facilities not included in category 4
* Buildings and other structures containing sufficient quantities of toxix or explosive substances to be dangerous to the public if released
Buildings and other structures designated as essential facilities including, but not limited to:
* Hospitals and other healthcare facilities having surgery or emergency
* Fire, rescue and police stations and emergency vehicle garages
* Designated earthquake, hurricane, or other emergency shelters
* Communications centers and other facilities required for emergency response
* Power generating stations and other public utility facilities required in an emergency
* Buildings and other structures having critical national defense functions