To address the concerns about nuclear power plant surveillance tests, i.e., their adverse safety impact due to negative effects and too burdensome requirements, it is necessary to evaluate the safety significance or risk effectiveness of such tests explicitly considering both negative and positive effects. This paper defines the negative effects of surveillance testing from a risk perspective, and then presents a methodology to quantify the negative risk impact, i.e., the risk penalty or risk increase caused by the test. The method focuses on two important kinds of negative effects, namely, test-caused transients and test-caused equipment degradations. The concepts and quantitative methods for the risk evaluation can be used in the decision-making process to establish the safety significance of the tests and to screen the plant-specific surveillance test requirements. 6 refs., 2 figs., 2 tabs