Full Description ADOPTED_FROM:EN ISO 1628-1:2009 ISO 1628-1:2009 defines the general conditions for the determination of the reduced viscosity, intrinsic viscosity and K‑value of organic polymers in dilute solution. It defines the standard parameters that are applied to viscosity measurement, and can be used to develop standards for measuring the viscosities in solution of individual types of polymer. It can also be used to measure and report the viscosities of polymers in solution for which no separate standards exist.