Lung volume is the amount of air normally breathed into and out of the lungs. Not smoking can help someone have a larger lung volume. Smokers tend to have smaller lung volumes. Human beings can retain 6 liters of air in the lungs at a given time. Lung volume may be negatively affected by scoliosis. Oxygen bars may be located at places at high altitudes. Those living in high altitudes tend to have higher lung volumes.