The fading of fast proton and μ-meson tracks in G5 nuclear emulsion has been studied as a function of time and conditions of storage. The storage time for a 50% reduction in the blob density of the tracks is estimated to be 1040 ± 200 days for storage at 5° C and 520 ± 50 days at 25° C. No difference in fading has been found between the emulsions stored in air and those stored in commercial argon. The mechanism responsible for the fading appears to be the thermal ejection of electrons from the latent image.The sensitivity of the emulsion after storage has also been studied. A reduction in blob density of the tracks of fast particles of less than 5% after a storage time of 450 days has been found.