Abstract: A sealing water agent can prevent evaporation of sealing water. Water alone is conventionally used for sealing water. An oil component and a surfactant can be used for the sealing water agent, which can be applied to a sealing water pipe, effectively preventing evaporation of the scaling water. All oil layers and all emulsified layers can be formed. As a result, the scaling water can be effectively prevented from evaporating. Furthermore, when the sealing water is discharged, the surfactant can emulsify the oil layer so that the sealing water agent can be discharged effectively.