A diagnostic system, comprising: a plurality of processors (300, 302, 304), wherein at least a portion of the processors are configured to receive data acquired by a sensor, the plurality of processors including, a first processor configured to, continuously execute one or more safety functions during a respective portion of a diagnostic interval, wherein each executed safety function is configured to perform operations including, determining one or more respective sensor measurements representing an operating parameter of a monitored asset from the received data; comparing selected ones of the one ore more respective sensor measurements to respective predetermined alarm set points; determining a safety function output for the selected sensor measurements based upon the sensor measurement comparison, the safety function output representing a first status estimate for the monitored asset; and transmitting the safety function output; characterized by a second processor configured to: execute a shadow function configured to determine one or more shadow function output each corresponding to a respective safety function output during a respective portion of a the diagnostic interval distinct from the respective portion of the corresponding safety function, and wherein each shadow function output represents a second status estimate for the monitored asset using the same data from the sensor as the corresponding safety function; and transmit each of the shadow function outputs for the safety function output; a third processor, different from the first and second processors (300, 302), and configured to: validate the one or more safety function outputs by comparing each of the safety function outputs with its corresponding one shadow function output, and output a condition for the monitored asset based upon the validation comparison; and a plurality of relays (52,54,56) configured to receive the output condition to actuate a respective relay contact (58,60,62) and transmit a condition signal representing the determined condition for annunciation. a first processor configured to, continuously execute one or more safety functions during a respective portion of a diagnostic interval, wherein each executed safety function is configured to perform operations including, determining one or more respective sensor measurements representing an operating parameter of a monitored asset from the received data; comparing selected ones of the one ore more respective sensor measurements to respective predetermined alarm set points; determining a safety function output for the selected sensor measurements based upon the sensor measurement comparison, the safety function output representing a first status estimate for the monitored asset; and transmitting the safety function output; determining one or more respective sensor measurements representing an operating parameter of a monitored asset from the received data; comparing selected ones of the one ore more respective sensor measurements to respective predetermined alarm set points; determining a safety function output for the selected sensor measurements based upon the sensor measurement comparison, the safety function output representing a first status estimate for the monitored asset; and transmitting the safety function output; characterized by a second processor configured to: execute a shadow function configured to determine one or more shadow function output each corresponding to a respective safety function output during a respective portion of a the diagnostic interval distinct from the respective portion of the corresponding safety function, and wherein each shadow function output represents a second status estimate for the monitored asset using the same data from the sensor as the corresponding safety function; and transmit each of the shadow function outputs for the safety function output; execute a shadow function configured to determine one or more shadow function output each corresponding to a respective safety function output during a respective portion of a the diagnostic interval distinct from the respective portion of the corresponding safety function, and wherein each shadow function output represents a second status estimate for the monitored asset using the same data from the sensor as the corresponding safety function; and transmit each of the shadow function outputs for the safety function output; a third processor, different from the first and second processors (300, 302), and configured to: validate the one or more safety function outputs by comparing each of the safety function outputs with its corresponding one shadow function output, and output a condition for the monitored asset based upon the validation comparison; and a plurality of relays (52,54,56) configured to receive the output condition to actuate a respective relay contact (58,60,62) and transmit a condition signal representing the determined condition for annunciation. validate the one or more safety function outputs by comparing each of the safety function outputs with its corresponding one shadow function output, and output a condition for the monitored asset based upon the validation comparison; and a plurality of relays (52,54,56) configured to receive the output condition to actuate a respective relay contact (58,60,62) and transmit a condition signal representing the determined condition for annunciation.