ANSI Standard IT9.9-1996 is commonly recommended for predicting dark storage print life for color photographic materials. This standard is based on Arrhenius methodology and calls for measuring changes in print density that occur as a function of temperature at 50%±3% relative humidity. The objective of this paper is to examine the dark keeping properties of inkjet photographic prints as a function of constant absolute humidity at various temperatures. The primary focus is on commercially available dye-based inks printed onto both porous and non-porous photo-quality papers.