A device for monitoring the health status of a limited life critical system , comprising: - at least one measurement sensor (S1-S6) adapted to measure a magnitude adapted to affect the health status of said critical system by outputting a signal carrying information relative to such magnitude; - at least one processing unit operatively connected to the sensor (S1-S6) 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 processing unit ; - a power supply system of the measurement sensor (S1-S4) and the processing unit ; - a communication interface adapted to transmit said stored digital data; wherein: - said device comprises a data displaying unit operatively connected to the processing unit and adapted to locally display data relative to the health status of said critical system and/or data relative to said magnitude; - the measurement sensor (S1-S6) comprises a temperature sensor, wherein the digital data comprise data related to a storage temperature of said critical system , and wherein the processing unit is programmed to calculate an equivalent storage time at a reference temperature; - the processing unit is programmed to calculate the equivalent storage time at a reference temperature by calculating an acceleration factor according to the Arrhenius law; characterized in that: - the data displaying unit comprises a bistable display; - the processing unit is programmed to control a refresh of the bistable display sporadically and on occurrence of a preset condition detectable by the processing unit ; and in that, in order to calculate said equivalent storage time, the 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. - at least one measurement sensor (S1-S6) adapted to measure a magnitude adapted to affect the health status of said critical system by outputting a signal carrying information relative to such magnitude; - at least one processing unit operatively connected to the sensor (S1-S6) 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 processing unit ; - a power supply system of the measurement sensor (S1-S4) and the processing unit ; - a communication interface adapted to transmit said stored digital data; - said device comprises a data displaying unit operatively connected to the processing unit and adapted to locally display data relative to the health status of said critical system and/or data relative to said magnitude; - the measurement sensor (S1-S6) comprises a temperature sensor, wherein the digital data comprise data related to a storage temperature of said critical system , and wherein the processing unit is programmed to calculate an equivalent storage time at a reference temperature; - the processing unit is programmed to calculate the equivalent storage time at a reference temperature by calculating an acceleration factor according to the Arrhenius law; - the data displaying unit comprises a bistable display; - the processing unit is programmed to control a refresh of the bistable display sporadically and on occurrence of a preset condition detectable by the processing unit ; - 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. <EOS>