Release dispersion simple evaluation techniques

The radioactivity inhaled by an exposed person during the passage of the contaminated cloud. 

In Gaussian theory of diffusion (the most commonly used), x is a function of wind speed (inverse proportionality), the values of the standard deviation of the Gaussian distribution, the height of release and the position of a point in space with reference to the release point. The relevant formulae and diagrams, valid within several tens of kilometres from the release point, are given in Section 6-4. For simplified evaluations that usefully support quick decisions, they are not strictly necessary. For now it is sufficient to know that the formulae and diagrams 

A - Extremely unstable conditions B - Moderately unstable conditions C - Slightly unstable conditions 

D - Neutral conditions (applicable to heavy overcast conditions, day or night) 

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