HEPA (High Efficiency Particulate Air) filtration is an air treatment technology for removing ultra-fine particles from an air stream. A conventional filter consists of a large sheet of corrugated filter medium sealed in a filter housing. The corrugated structure increases surface area of the media and reduces the pressure drop across the filter. Although very expensive metal HEPA filters exist, typically the filter medium is non-woven paper, polymer, or fiberglass microfibers. These materials degrade under non-ambient conditions, which limits their use in industrial high temperature, corrosive and flammable settings, where a leak could cause serious hazards.  LLNL has invested over a decade in the design of ceramic HEPA filters for the nuclear industry to address fire and corrosion concerns.  The advantage of ceramic nanofibrous structures, including 3D-printed structures has been clear to LLNL researchers. However, the technology development lags behind the technology of developing nanofibrous materials of other compositions.  The main challenge for developing the ceramic materials is shrinkage and embrittlement associated with the thermal treatments required to convert pre-ceramic precursors into ceramics.