A device for monitoring the health status of a limited life critical system, which undergoes ageing according to a variation of its internal temperature over time, comprising: - at least one measurement sensor (S1-S4) adapted to measure a magnitude adapted to affect the health status of the critical system by outputting a signal carrying information relative to such magnitude, wherein the measurement sensor (S1-S4) comprises a temperature sensor configured to measure an external temperature of the critical system; - at least one processing unit operatively connected to the sensor (S1-S4) and adapted to receive and sample said signal to provide digital data relative to such magnitude; - at least one memory adapted to store said digital data or digital data obtained therefrom through said at least one processing unit; - a power supply system of the measurement sensor (S1-S4) and the processing unit; Characterized in that: - said device further includes a passive RFID transponder adapted to receive a request from an external query RFID device (4,8) from remote, and to provide as a reply said digital data to the query device (4,8) by accessing the memory; and - the digital data comprise data related to the storage temperature of the critical system, and wherein the at least one processing unit is programmed to calculate an equivalent storage time at a reference temperature by calculating an acceleration factor according to the Arrhenius law, the equivalent storage time being representative of the residual life of the critical system; Wherein in order to calculate said equivalent storage time the at least one processing unit is programmed for: - Sampling said signal to obtain a digital sample and storing it in a vector of samples having a predetermined length according to a FIFO storage technique; - Upon each sampling, carrying out the scalar product between said vector of samples and a vector of real numbers, which represent exponential increment values depending on the internal temperature as obtained from the samples of the external temperature measured by the temperature sensor. - at least one measurement sensor (S1-S4) adapted to measure a magnitude adapted to affect the health status of the critical system by outputting a signal carrying information relative to such magnitude, wherein the measurement sensor (S1-S4) comprises a temperature sensor configured to measure an external temperature of the critical system; - at least one processing unit operatively connected to the sensor (S1-S4) and adapted to receive and sample said signal to provide digital data relative to such magnitude; - at least one memory adapted to store said digital data or digital data obtained therefrom through said at least one processing unit; - a power supply system of the measurement sensor (S1-S4) and the processing unit; - said device further includes a passive RFID transponder adapted to receive a request from an external query RFID device (4,8) from remote, and to provide as a reply said digital data to the query device (4,8) by accessing the memory; and - the digital data comprise data related to the storage temperature of the critical system, and wherein the at least one processing unit is programmed to calculate an equivalent storage time at a reference temperature by calculating an acceleration factor according to the Arrhenius law, the equivalent storage time being representative of the residual life of the critical system; - Sampling said signal to obtain a digital sample and storing it in a vector of samples having a predetermined length according to a FIFO storage technique; - Upon each sampling, carrying out the scalar product between said vector of samples and a vector of real numbers, which represent exponential increment values depending on the internal temperature as obtained from the samples of the external temperature measured by the temperature sensor.