External air processing device for nuclear power plant

In an external air processing device disposed to an external air intake conditioning facility of a nuclear power plant building, a heating means for melting snow is disposed between an outer side of the building and an external air processing/outputting section of the external air processing device. The external air processing device comprises a static charge device having an electric discharge wire and a cathode having a heating means opposed to the electric discharge wire and a filter for removing charged particles. A circular channel allowing a heat medium to pass therethrough is disposed at least to a portion of the cathode. With such a constitution, snow introduced from the outside of the building while mixed into an external air is heated and melted by the heating means before coming out of the external air processing device and not accumulated for a long period of time. In addition, since the static charge device also has a function of a snow melting device, the device is made compact with no addition of a device which requires additional space. Further, stable heating/snow melting performance is conducted uniformly with less local heating corresponding to a heat medium phase. (T.M.)