Background: Modernization has been implicated in the pathogenesis of allergic airway diseases. House dust, mites, and indoor air pollutants have been reported to cause elevation of serum IgE levels and/or enhancement of eosinophil activity. A component of modern lifestyle is the intense use of air-conditioners (AC) that has increased the risk of atopic sensitization. Aim: To assess the effect of air conditioners on pulmonary function tests in healthy non-smokers. Methods: The study included 100 subjects using AC and 100 subjects who were not using AC. After ethical committee approval, pulmonary function tests were done for both study groups by using Medspiror. The data obtained was tabulated and analyzed. Results: The lung functions particularly Forced vital capacity (FVC), and Forced expiratory volume in 1 second (FEV 1) , were affected more in AC users. FVC and FEV 1 were found to be significantly reduced and FEV 1 /FVC was found to be normal. Conclusion: As FVC and FEVFEV 1 were found to be significantly reduced and FEV1/FVC was found to be normal, this is suggestive of predisposition of AC users towards restrictive type of respiratory disorders.