Effective community messaging is a challenging and ongoing area of investigation within the emergency management sector. In an attempt to evoke compliance, the public are repeatedly exposed to warnings which convey risk information. However, these warnings are often ignored which can result in situations with catastrophic outcomes. Thus, there is an urgent need to identify the reasons behind this non-compliance. One such reason that requires further investigation is that of message wear-out or message fatigue. In fact, recent research has made a recommendation to emergency management professionals to not ‘over-warn’ through repeatedly alerting the public about a single event (Vermeulen, 2014). However, this poses the question: How many times should the public be exposed to warnings before their effectiveness begins to wane? This question could be addressed by exploring the mere exposure effect to the disaster warnings. The mere exposure effect has been documented as a robust a reliable phenomenon (Bornstein, 1989) and refers to the observation that repeated, unreinforced exposure to a stimulus increases affective evaluations of that stimulus (Zajonc, 1968). Put simply, the more familiar a person is with a given stimulus, the more they are reported to like it. The stimuli used in mere exposure studies are typically neutral and meaningless, with meaningful, and in particular, emotionally-valenced stimuli relatively overlooked. This is a significant oversight given that many of today’s warnings are based on repeatedly exposing people to aversive or threatening stimuli in an attempt to reduce their affective evaluations towards them: the very opposite of what the mere exposure hypothesis would predict. This leaves questions open regarding whether or not the usual attitude-enhancing effects of repeated exposure found for neutral stimuli would also apply to aversive emergency stimuli. A recent study conducted by Aimers (2015) sought to investigate the effects of controlled, repeated exposure on subsequent affective evaluations of aversive stimuli, specifically, cigarette health warning images. Within this study, it was identified that participant liking ratings actually began to significantly increase after their initial exposure. Likewise, the health warnings also became significantly less unpleasant and arousing following only two exposures. Hence, given that both health and disaster warnings are designed to be attention grabbing and provide directive instruction to influence behaviour, the findings of Aimers (2015) suggest that the intended behaviours are not always elicited as a result of repeated exposure, possibly due to message wear-out or fatigue. We argue that these findings could extend to other types of emergency warnings. Therefore, emergency professionals need to be aware of the possibility that warnings can be susceptible to the effects of repeated exposure (i.e., the mere exposure effect). As a consequence, consideration of how often the design of emergency warnings needs to be updated and refreshed to retain message efficacy is required.