This paper analyzes whether or not different non-tariff measures (NTM) like a standard or a mandatory label can be considered as protectionist in presence of market imperfections. From a welfare-based approach, protectionism occurs when the instrument maximizing domestic welfare is different from the alternative instrument maximizing international welfare inclusive of foreign profits. A framework taking into account different tools shows the complexity for characterizing protectionism related to different NTM. When the standard impacts variable costs, the mandatory label can be protectionist. When the standard impacts sunk costs, the standard can be protectionist. The framework is also useful for empirically characterizing the impact of NTM related to a specific product. An application to shrimp trade illustrates the feasibility of the welfare measure, for an ex ante evaluation of possible environmental regulations that could be implemented in the future. This application confirms that the tool maximizing domestic welfare does not systematically correspond to the tool maximizing international welfare.