ARDS acute respiratory distress syndrome BAL bronchoalveolar lavage CO carbon monoxide CO 2 carbon dioxide CT computed tomography D LCO diffusing capacity of the lung for carbon monoxide F ENO exhaled nitric oxide fraction FEV 1 forced expiratory volume in 1 s FVC forced vital capacity HRCT high-resolution computed tomography IPF idiopathic pulmonary fibrosis LEV local exhaust ventilation NO 2 nitrogen dioxide NO X oxides of nitrogen O 2 oxygen PaO 2 arterial O2 tension PEF peak expiratory flow PET positron emission tomography PM particulate matter UIP usual interstitial pneumonia VOC volatile organic compound List of abbreviations