The normal cervical dilation rate plotted on the partograph is 1 cm/hour during the active phase of labor. This rate reflects the average progress needed to ensure timely delivery and prevent labor dystocia. Monitoring dilation at this rate helps clinicians identify abnormal labor patterns early, allowing for appropriate interventions. A slower rate may indicate prolonged labor, increasing the risk of maternal and fetal complications. The partograph's alert line is drawn with a slope of 1 cm/hour, serving as a crucial visual guide in labor management.

Reference: Williams Obstetrics, Cunningham et al., 25th Edition.