The impact created by human activity can produce marine debris and affect the marine environment. 181 U.S. divers were tested for their current household practices regarding discarding plastic and food waste, providing quantitative statistics for divers‟ referential behaviour. 30% of all divers involved in the study participated in a web survey analysing the long-term impacts from scuba diving activity. Adapted from the theory of planned behaviour, post-experience observations were used for a two-step cluster analysis, which demonstrated that environmental awareness and attitude toward the behaviour can be important predictors for reducing the amount of plastic and food discards in the household. Being a member of an environmental organization does not affect waste management practices, and scuba diving is not a blueprint for behavioural change; however, it definitely plays an important role in creating an awareness of and observing the impacts on the reef. Thus, scuba diving is only characterized as a good vehicle for promoting good environmental practices for discarding plastic and food, motivating people to rethink their attitudes toward their behaviour in the household.