An emergency eyewash station is disclosed. When updating TDMS, an update reason of a corresponding TDMS and a TDDS start address in a previously recorded TDMS are recorded in disc management information as additional information. When the target signal is unknown, the computer also processes the simultaneously obtained samples of the target signal to estimate the bandwidth of the received target signal by using binary hypotheses and a generalized log likelihood ratio test or by using multiple hypotheses and pair-wise generalized log likelihood ratio tests.