The present study was performed to assess the sub-acute safety and efficacy study of sub-micronized aerosols of sodium nitrite respiratory fluid. Nebulization of sodium nitrite respiratory fluid (1, 3 and 5 %) was carried out in Sprague Dawley rats as per regulatory guidelines using nebulization assembly. Animals were sacrificed and analyzed for hematological, biochemical and organ histopathology parameters. Bronchoalveolar lavage (BAL) fluid was collected and different biochemical markers were measured. No drug related toxicity on morphological or biochemical parameters was seen at any of the drug concentration studied. Histopathological analysis of lung tissues revealed no inflammatory responses, except for vasodilatation of alveoli, which is the desired effect of the drug. For efficacy study sodium nitrite respiratory fluid was inhaled to animals in which oxidative stress and lung injuries were induced by smoke inhalation. There was significant increase in protein concentration, neutrophils, airway epithelia in the BAL, and lung microvasculature changes were evident in experimental animals post smoke inhalation. Pre-treatment with sodium nitrite respiratory fluid decreased airway necrosis, lung edema and alveolar protein leak induced by smoke inhalation. The study highlights the prophylactic potential of sodium nitrite nebulization against oxidative stress and lung injury caused due to smoke inhalation, and could be significant in developing a novel prophylactic/ therapeutic option for victims as well as members of the rescue team, including firefighters.