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11.2 General Gaussian Dispersion Model 325

Stable
F

stable

Slightly

E cloud
or
Clear – F E D D

Neutral
D

>4/8
or
unstable time overcast

Slightly Night Thinly cloud

C – E D D D
conditions

weather Slight B C C D D

corresponding B Moderately unstable

and radiation A–B B B–C C–D D
classes solar

stability A Extremely unstable time Day Incoming Strong A A–B B C C

Pasquill

11.1 (m/s)

Table class P Stability u 10 Moderate 0–2 2–3 3–5 5–6 >6