Question

What is residual volume of air?

Answer 1

residual volume is amount of air that remains in a person's lung after fully exhalling Doctor used to measure of person residual air volume to have check how well the lungs are functioning residual volume is measured by a gas dilution test.
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Answer 2

Residual volume (RV) is the amount of air that remains in a person’s lungs after maximum exhalation. In other words, this is the volume of air that we can’t possibly get out of our lungs, meaning that the lungs are never completely empty of air. Otherwise, they would collapse as the tissue sticks together. On average, a person’s RV is about a liter and doctors can run special tests to find a person’s RV, as it can indicate lung health.