An object of the present invention is to provide a planar structure with improved sterilization performance of airborne bacteria in the air while realizing safety and space saving when applied to a structure of an indoor space. The sheet heating element 10 includes a sheet-like conductive layer 20 that generates heat when energized, and insulating coating layers 30 and 40 that insulate and coat the front and back sides of the conductive layer 20. In the planar heating element 10, the insulating coating layer 30 includes a weak radiation-generating ore powder 50. According to this, the density concentration of a positive ion and a negative ion increases rather than the case where the sheet seat which disperse distributed the powder 50 of the weak radiation generation ore is only placed in the indoor space of a building, and the disinfection performance of the floating bacteria in an indoor space Can be improved. [Selection] Figure 1【課題】屋内空間の構造体に適用した際の安全性、省スペース化を実現しつつ空気中の浮遊細菌の殺菌性能を向上させた面状構造体を提供すること【解決手段】建物の屋内に設置され、通電により発熱する面状の導電性層２０及び導電性層２０の表面側及び裏面側を絶縁被覆する絶縁被覆層３０，４０を有する面状発熱体１０である。面状発熱体１０は、絶縁被覆層３０が微弱放射線発生鉱石の粉末５０を含む。これによれば、単に微弱放射線発生鉱石の粉末５０を分散させたシートを建物の屋内空間中に置いた場合よりも正イオン及び負イオンの濃度が増加し、屋内空間中の浮遊細菌の殺菌性能を向上させることができる。【選択図】図１
