In nanometer technologies, capacitive coupling between signal lines is increasing, thereby causing crosstalk-induced hazards. Crosstalk analysis and avoidance methodologies have evolved to tackle this problem through various stages of the design flow. To effectively avoid crosstalk and identify circuits failing due to crosstalk noise, certain noise related parameters have to be characterized for the cells in the technology library. Characterization of noise parameters such as noise immunity and propagation accounts for about 60% of the total ASIC library characterization cycle time, and hence becomes a bottleneck in the library creation process. In this paper we present a comprehensive methodology that enables noise characterization of nanometer libraries in reasonable time.