Wind Speed Chart

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Design of safe flagpoles requires knowledge of the loads to which they will be subjected. The principal load acting on flagpoles is wind load and that load must be carefully determined.

Maximum wind speeds to which flagpoles are exposed depend on geographical loaction, whether or not it is in the centre of a large city, a small town's outskirts, seashore, at ground level or on the roof of a high building. Wind speeds generally are higher along coastal areas than inland. They are also higher in open country than in the centre of cities. Wind speed becomes greater as the height above ground increases.

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Wind exerts a force on the pole as well as the flag, thus both loads must be added together to determine the total load. Flags of different sizes are designed to be flown from different poles. Obviously, it is important that flagpoles are selected which are capable of supporting the largest flag intended to be flown in the highest wing speed to which it will be subject.