A measure of the power consumption of the shaft of an agitator used to mix a liquid in a stirred tank or agitated vessel. Agitation intensities are expressed (p. 8) as the power supplied per unit volume of liquid. The SI units are W m^–3. The magnitude of the agitation intensity is dependent on the nature of the liquid being stirred. Biological solutions containing flocculating materials are significantly affected by the level of agitation.