<p>CBRN threats pose a hazard depending on the type of amount, or duration of exposure. In the event of any CBRN hazard being exposed, respiratory protection is required to prevent inhalation of these hazards. Biodegradable nanofiber filters are of great interest to reduce plastic waste and promote sustainability. This study aimed to produce green air filters using cellulose considered an inexhaustible source of raw materials. Cellulose nanofiber filters were produced by the electro-spinning method by coating on medical crepe and melt-blown fabric. Air permeability, pressure drop, filtration efficiency, strength properties, and filtration properties against toxic gases such as formaldehyde were investigated in CBRN filters. Whether CBRN filters have a harmful effect on healthy bronchial epithelial cells (BEAS-2B) was investigated by the Alamar Blue method in in vitro conditions. In addition, the bacterial growth capacity of the filters in <i>S.aureus</i>, <i>E.coli</i>, and <i>S.epidermis</i> species was examined. Nanofiber filters, which were successfully produced in diameters of 300–600&#xa0;nm, had good air permeability (29 m³h⁻¹) and PM_0.3 (93, 19%) particle retention. No toxicity was observed on healthy bronchial epithelial cells, and inhibited viability of the most abundant bacteria in the air. As a result, the developed nanofiber CBRN air filters will be extremely valuable for the next generation of military protection due to their superior properties.</p> Graphical abstract <p></p>