NaturalHazards.org
The Saffir-Simpson Hurricane Damage Potential Scale was developed at the National Hurricane Center in the early 1970's.

Category

Wind speed range

Central Pressure Storm surge

Damage level

1 74 to 95 mph (119 to 153 kph) (64 to 82 knots) greater than 28.93 in. (980 mb) 4 to 5 ft (1.5 m) minimal: trees and shrubs damaged, unanchored mobile homes damaged.
2 96 to 110 mph (154 to 177 kph) (83 to 95 knots)

28.50 to 28.91 in. (965 to 979 mb)

6 to 8 ft (2.0 - 2.5 m) moderate: trees blown down, some damage to buildings.
3 111 to 130 mph (178 to 209 kph) (96 to 113 knots) 27.91 to 28.47 in. (945 to 964 mb) 9 to 12 ft (2.5 to 4.0 m) extensive: large trees blown down, mobile homes destroyed, structural damage to small buildings.
4 131 to 155 mph (210 to 249 kph) (114 to 135 knots) 27.17 to 27.88 in. (920 to 944 mb) 13 to 18 ft (4.0 to 5.5 m) extreme: complete destruction of mobile homes, damage to windows, doors, and roofs of buildings, flooding for several miles (kilometers) inland.
5 greater than 155 mph (249 kph) (135 knots) less than 27.17 in. (920 mb) greater than 18 ft (5.5 m) catastrophic: small buildings destroyed, severe damage to large buildings, extensive inland flooding.