| Sound | Description |
|---|
| Crackles | Light crackling, popping, intermittent nonmusical sounds — like hairs being rubbed together — heard on inspiration or expiration |
| Pleural friction rub | Low-pitched, continual, superficial, squeaking or grating sound — like pieces of sandpaper being rubbed together — heard on inspiration and expiration |
| Rhonchi | Low-pitched, monophonic snoring sounds heard primarily on expiration but also throughout the respiratory cycle |
| Stridor | High-pitched, monophonic crowing sound heard on inspiration; louder in the neck than in the chest wall |
| Wheezes | High-pitched, continual musical or whistling sound heard primarily on expiration but sometimes also on inspiration |