Describes a procedure for determining the viscosity of coating materials and related products at a rate of shear not less than 5000 s-1 and not higher than 20000 s-1. When products are being compared the rate of shear shall be approximately the same. The test shall be made at a closely controlled temperature unless otherwise agreed. The value obtained gives information about the resistance of the material to brushing during the initial application. The method is suitable for all brushing paints and varnishes. More reproducible for paints having low values for fineness of grind as determined by ISO 1524.