During Liquid Composite Molding, a fibrous reinforcement is impregnated with liquid resin. Process design requires
knowledge of the reinforcement permeability for fluid flow, but until recently, there has been no standard
available for its measurement. In 2023, following decades of benchmarking activities and a standardization
project, an ISO standard for the experimental characterization of in-plane permeability of fibrous reinforcements
for liquid composite molding was finally published. It focuses on the experimental characterization of unsaturated
in-plane permeability and specifies the requirements for test equipment, methods and data analysis. Given
the deficiency of standardized procedures within the composites industry, this paper intends to provide an
example of the steps towards standardization and summarizes lessons learned. It illustrates the research milestones
that led to the establishment of the standard, promotes the standard by detailing its general content and
notable features and finally gi