ASTM D445 & IP71
The ASTM D445, IP 71 and ISO 3104 test methods specifies a procedure for the determination of the kinematic viscosity of liquid petroleum products, both transparent and opaque. Examples are kerosene, bitumen, waxes, fuel oils, diesel, gas oils, lubricants, residual oils, transformer oils, biodiesel, and used oils. The time is measured for a fixed volume of liquid to flow under gravity through the capillary of a calibrated viscometer under a reproducible driving head and at a closely controlled and known temperature inside a viscosity bath. The kinematic viscosity (determined value) is the product of the measured flow time and the calibration constant of the viscometer. Two such determinations are needed from which to calculate a kinematic viscosity result that is the average of two acceptable determined values.