High humidity is one of the causes of print degradation particularly for prints in consumer homes. The study made on a typical set of ink-jet media and several commercial ink sets looks at ways to characterize the humidity sensitivity of such ink/media systems. In a first step, several factors influencing print degradation at high humidity were investigated. In a second step, a closer look was taken at the onset point where humidity degradation becomes objectionable. Sharpness and colour change metrics on the test image were compared to visual ranking of pictorial prints that had undergone the same humidity exposure. The Cielab DE difference on a checkerboard pattern exposed to varying levels of humidity is the most sensitive indicator to determine the threshold at which first image degradation occurs.