Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP , upright portable chest radiograph obtained . The lungs are clear bilaterally without focal consolidation , effusion , or pneumothorax . No signs of pneumomediastinum . Heart and mediastinal contours are normal . No free air below the right hemidiaphragm . Bony structures are intact .
    OUTPUT:
    
No evidence of free air .