Q. Show Prevailing wind conditions for plant layout?

Prevailing wind conditions influence the design considerations for the location of the flare or vent stack. It is vital that reliable wind data is obtained for the proposed location of the facility. In this respect, safe design requirements will typically require the following:

• That the plant is safely ventilated.

• Safe areas and locations are provided that are up-wind of any potential hazardous releases.

• Any plumes of airborne gas and/or particulates are dissipated away from critical areas of the plant and other occupied/public areas as effectively as possible by the prevailing wind.

• Radiant heat emission levels from flares, and/or accidental ignition of vents.

Prevailing wind conditions also influence the placement of uncovered stockpiles of bulk solids which can be a source of dust. Because prevailing wind direction impacts on so many dependent design decisions, it shall be included on all site/plot plans. Metrological wind data is normally presented in the form of a "Wind Rose".

The "Rose" defines the direction of winds and expected frequency of wind velocity from each wind direction in a typical year or identified seasonal periods. Accompanying wind frequency tables provide data on expected wind speed occurrences from calm to extreme conditions.