Abstract: In order to enhance the operation efficiency of tritiated wastewater air carrying discharge facilities and to ensure its safety operation, the effects of environmental temperature, relative air humidity and induced air volume on the amounts of air carrying discharge of tritiated wastewater were analyzed by using the principle of air humidification. The analytical results indicate that induced air volume, relative air humidity and temperature are three main factors affecting the emission of tritiated wastewater in this facility. And the induced air volume plays a main dual role than the other two factories due to it can enhanc the convective heat transfer of tritiated wastewater and increase the total driving force of evaporation. Compared with the influence of evaporation enthalpy difference of tritiated wastewater caused by temperature increase, the influence of total driving force of tritiated wastewater evaporation caused by air relative humidity increase is greater. The above mentioned three factors should be considered during the design phase of the similar type of air carrying discharge facilities. The environmental meteorological conditions suitable for the operation of the facilities were demonstrated through analysis continue 4 years operation data of the facility by using wet-enthalpy (H-I) relationship. The suitable operating climatic conditions for the facilities are temperature of 18-26 ℃ and relative air humidity of 30%-35%. It is suggested that to extend the daytime running time in April and May when the above environmental conditions are met to improve the efficiency of tritiated wastewater airborne discharge. Based on these research results, some suggestions are also put forward on how to resolution some operation problems which frequently occurred during the facility operation, such as unsuitable arrangement of air flow distribution, clogging of air inlet filter and overflow of catchment tank etc.