Definition: The amount of air which can be forcibly exhaled from the lungs in the first second of a forced exhalation. Measuring FEV1 is done through spirometry testing which helps your doctor determine your lung function.
Because COPD causes the air in your lungs to be exhaled at a slower rate and in a smaller amounts compared to a normal, healthy person, measuring how well you can forcibly exhale air can help determine the presence of COPD.
Also Known As: FEV1, FEV1%
