Principle of liability without fault has special stipulations on the applicable objects; it does not take the faults of the person causing the injury into consideration. Tortious act has the characteristics of the injurious act, damage and the causal relationship between them. 无过错责任原则具有适用对象特别规定,不考虑加害人的过错,侵权行为由侵害行为、损害及二者之间的因果关系构成的特征。