A processing system for alerting an on-duty operator of the need to transfer operational control to an off-duty operator, comprising: a first set of sensors for disposition at least adjacent to the on-duty operator and in operable communication with the processor, wherein the first set of sensors comprises one or more video sensors, one or more seat load sensors and one or more electrocardiogram sensors; and a second set of sensors for disposition at least adjacent to the off-duty operator and in operable communication with the processor, wherein the second set of sensors comprises: one or more electroencephalogram sensors; one or more electrooculogram sensors; and one or more inertial sensors, a flexible substrate configured to be worn on a head of the off-duty operator, wherein the second set of sensors is coupled to the flexible substrate, and wherein the flexible substrate is configured as a blindfold to be worn by the off-duty operator; a processor, configured to: receive first physiological and activity data from the first set of sensors, the first physiological and activity data including data representative of facial features, body and facial movements, posture, in-seat activity, and heart rate; utilizing the data representative of facial features, body and facial movements, posture, in-seat activity, and heart rate to determine a measure of a fatigue state of the on-duty operator; receive second physiological and activity data from the second set of sensors, the second physiological and activity data including data representative of sleep duration, sleep phase, and time in, or since, a particular sleep phase; utilizing the data representative of sleep duration, sleep phase, and time in, or since, a particular sleep phase; to determine a measure of a rest state of the off-duty operator; compare the measure of the fatigue state of the on-duty operator to a predetermined fatigue state threshold; compare the measure of the rest state of the off-duty operator to a predetermined rest state threshold; generate an alert signal indicating that the on-duty operator should transfer operational control to the off-duty operator when (i) the fatigue state of the on-duty operator exceeds the predetermined fatigue state threshold or (ii) the rest state of the off-duty operator exceeds the predetermined rest state threshold; and an alert generator coupled to receive the alert signal from the processor and configured, upon receipt of the alert signal, to generate an alert indicating that the on-duty operator should transfer operational control to the off-duty operator. a first set of sensors for disposition at least adjacent to the on-duty operator and in operable communication with the processor, wherein the first set of sensors comprises one or more video sensors, one or more seat load sensors and one or more electrocardiogram sensors; and a second set of sensors for disposition at least adjacent to the off-duty operator and in operable communication with the processor, wherein the second set of sensors comprises: one or more electroencephalogram sensors; one or more electrooculogram sensors; and one or more inertial sensors, a flexible substrate configured to be worn on a head of the off-duty operator, wherein the second set of sensors is coupled to the flexible substrate, and wherein the flexible substrate is configured as a blindfold to be worn by the off-duty operator; receive first physiological and activity data from the first set of sensors, the first physiological and activity data including data representative of facial features, body and facial movements, posture, in-seat activity, and heart rate; utilizing the data representative of facial features, body and facial movements, posture, in-seat activity, and heart rate to determine a measure of a fatigue state of the on-duty operator; receive second physiological and activity data from the second set of sensors, the second physiological and activity data including data representative of sleep duration, sleep phase, and time in, or since, a particular sleep phase; utilizing the data representative of sleep duration, sleep phase, and time in, or since, a particular sleep phase; to determine a measure of a rest state of the off-duty operator; compare the measure of the fatigue state of the on-duty operator to a predetermined fatigue state threshold; compare the measure of the rest state of the off-duty operator to a predetermined rest state threshold; generate an alert signal indicating that the on-duty operator should transfer operational control to the off-duty operator when (i) the fatigue state of the on-duty operator exceeds the predetermined fatigue state threshold or (ii) the rest state of the off-duty operator exceeds the predetermined rest state threshold; and an alert generator coupled to receive the alert signal from the processor and configured, upon receipt of the alert signal, to generate an alert indicating that the on-duty operator should transfer operational control to the off-duty operator.