All appeals are dismissed.

The costs of appeal are assessed against the plaintiffs.

The grounds of appeal are examined.

1. Article 758(1) of the Civil Act provides, “If a loss is inflicted on another person due to a defect in the construction or preservation of a structure, the possessor of the structure shall be liable to compensate for the loss: Provided, That if the possessor does not neglect due care necessary for the prevention of loss, the owner shall be liable to compensate for the loss.”

Unlike the general tort as above, it is based on the principle of risk liability to impose interim liability with which the burden of proof of negligence has been converted on the possessor, and to increase liability on the owner by imposing strict liability.

In other words, the management owner of a structure must pay attention to the prevention of danger, and it is fair to impose liability on them when damage occurs due to the reality of risk.

Therefore, “defect in the installation and preservation of a structure” refers to a state in which a structure does not have safety ordinarily according to its intended purpose. In determining whether such safety is satisfied, it shall be determined on the basis of whether the installation and preservation manager of the structure fulfilled his/her duty to take protective measures to the extent generally required by social norms in proportion to the risk of the structure.

(2) In light of the aforementioned legal principles and legislative purport, and the standards for determining the defect in the installation and preservation of a structure, etc., even if a certain damage was incurred due to a defect in a structure, if the damage did not occur due to a realization of the risks associated with the defect in the structure, it cannot be deemed as “damage caused by a defect in the installation or preservation of a structure.”

2. According to the records, the plaintiffs were tap water at the time of the defendant's old Si due to the instant accident that occurred in the temporary structures.