This test method details the standard procedure for measuring the viscosity of resin solutions. The apparatuses required here are constant-temperature water bath, wide-mouthed screw capped bottles, cellophane sheets, No. 2 short taper corks, viscosity tube holder, bottle shaker, timing device, and viscosity tubes. Solid resins are dissolved in organic solvents by cold-cut or hot-cut methods in the laboratory. The viscosity of such prepared solutions, or of commercial solutions of resins is then determined by the bubble time method. The bubble seconds are approximately equal to stokes.