Evaluative information about appropriate use conditions is a necessary component of managing impacts in recreation settings. Social norm theory, which suggests there may be group agreement about appropriate conditions, can be applied to help establish standards. Norms were identified and measured using data from the white water rafting visitors on the Hsiukuluan River to empirically illustrate the application of the model to a recreation setting. The rafters were grouped into three homogenous subgroups according to their motives. Results show that: an encounter norm can be identified and conformed in the self-pursuit subgroup; but there is less shared agreement for those without particular motives and for those focusing on social relationship.