DESIGN FORCE, F: Equivalent static force to be used in the determination of wind loads for open buildings and other structures.
DESIGN PRESSURE, p: Equivalent static pressure to be used in the determination of wind loads for buildings.
EAVE HEIGHT, h: The distance from the ground surface adjacent to the building to the roof eave line at a particular wall. If the height of the eave varies along the wall, the average height shall be used.
EFFECTIVE WIND AREA, A: The area used to determine GCp. For component and cladding elements, the effective wind area in Figs. 6-11 through 6-17 and Fig. 6-19 is the span length multiplied by an effective width that need not be less than one-third the span length. For cladding fasteners, the effective wind area shall not be greater than the area that is tributary to an individual fastener.
ESCARPMENT: Also known as scarp, with respect to topographic effects in Section 6.5.7, a cliff or steep slope generally separating two levels or gently sloping areas (see Fig. 6-4).
FREE ROOF: Roof with a configuration generally conforming to those shown in Figs. 6-18A through 6-18D (monoslope, pitched, or troughed) in an open building with no enclosing walls underneath the roof surface.
GLAZING: Glass or transparent or translucent plastic sheet used in windows, doors, skylights, or curtain walls.
GLAZING, IMPACT RESISTANT: Glazing that has been shown by testing in accordance with ASTM El 886 and ASTM El 996 or other approved test methods to withstand the impact of wind-bome missiles likely to be generated in wind-bome debris regions during design winds.
HILL: With respect to topographic effects in Section 6.5.7, a land surface characterized by strong relief in any horizontal direction (see Fig. 6-4).
HURRICANE PRONE REGIONS: Areas vulnerable to hurricanes; in the United States and its territories defined as
1. The U.S. Atlantic Ocean and Gulf of Mexico coasts where the basic wind speed is greater than 90 mi/h, and
2. Hawaii, Puerto Rico, Guam, Virgin Islands, and American Samoa.
IMPACT RESISTANT COVERING: A covering designed to protect glazing, which has been shown by testing in accordance with ASTM El 886 and ASTM El 996 or other approved test methods to withstand the impact of wind-bome debris missiles likely to be generated in wind-bome debris regions during design winds.
IMPORTANCE FACTOR, /: A factor that accounts for the degree of hazard to human life and damage to property.
MAIN WIND-FORCE RESISTING SYSTEM (MWFRS):
An assemblage of structural elements assigned to provide support and stability for the overall structure. The system generally receives wind loading from more than one surface.
MEAN ROOF HEIGHT, h: The average of the roof eave height and the height to the highest point on the roof surface, except that, for roof angles of less than or equal to 10°, the mean roof height shall be the roof heave height.
OPENINGS: Apertures or holes in the building envelope that allow air to flow through the building envelope and that are designed as "open" during design winds as defined by these provisions.

RECOGNIZED LITERATURE: Published research findings and technical papers that are approved.
RIDGE: With respect to topographic effects in Section 6.5.7 an elongated crest of a hill characterized by strong relief in two directions (see Fig. 6-4).
WIND-BORNE DEBRIS REGIONS: Areas within hurricane prone regions located:
1. Within 1 mile of the coastal mean high water line where the basic wind speed is equal to or greater than 110 mi/h and in Hawaii, or
2. In areas where the basic wind speed is equal to or greater than 120 mi/h.
6.3 SYMBOLS AND NOTATION
The following symbols and notation apply only to the provisions of Chapter 6:
A = effective wind area, in ft2 (m2) Af = area of open buildings and other structures either normal to the wind direction or projected on a plane normal to the wind direction, in ft2 (m2) Ag = the gross area of that wall in which Ao is identified,
in ft2 (m2)
Agi = the sum of the gross surface areas of the building envelope (walls and roof) not including A^, in ft2 (m2)
Ao = total area of openings in a wall that receives positive external pressure, in ft2 (m2)
An; = the sum of the areas of openings in the building envelope (walls and roof) not including Ao, in ft2 (m2)
Agg = total area of openings in the building envelope in
ft2 (m2) A, = gross area of the solid freestanding wall or solid sign,
in ft2 (m2)
a =• width of pressure coefficient zone, in ft (m) 5 = horizontal dimension of building measured normal to wind direction, in ft (m)
5 = mean hourly wind speed factor in Eq. 6-14 from Table 6-2
&~= 3-s gust speed factor from Table 6-2 Cf = force coefficient to be used in determination of wind
loads for other structures cn = net pressure coefficient to be used in determination of
wind loads for open buildings
Cp = external pressure coefficient to be used in determination of wind loads for buildings c = turbulence intensity factor in Eq. 6-5 from Table
6-2
D = diameter of a circular structure or member, in ft (m) D' = depth of protruding elements such as ribs and spoilers,
in ft (m)
F = design wind force for other structures, in Ib (N) G = gust effect factor Gf = gust effect factor for MWFRSs of flexible buildings
and other structures GCpn = combined net pressure coefficient for a parapet
GCp = product of external pressure coefficient and gust-effect factor to be used in determination of wind loads for buildings

22	ASCE 7-05