The present disclosure provides a sensor system that includes a blood access device, a flow controller, and an analyte sensor. The system is configured to flush or draw a volume of fluid through the blood access device at least once； determine a signal-time history corresponding to signals received from the sensor； determine a duration of a portion of the signal-time history； determine whether the duration is greater than a predetermined threshold value； and detect the occlusion in the blood access device when the duration is greater than the predetermined threshold value.
