NBRC Normal Values TMC Practice Test

FEF 200-1200 is the average flow during the middle portion of a forced expiration, specifically from 200 mL to 1200 mL of exhaled air. It reflects large to upper airways function and is reported as a flow rate in liters per second. The normal value is about 6.0 L/sec, or 80% of the predicted value or higher for the patient. This makes the option with 6.0 L/sec or 80% predicted or higher the best choice, because it fits the typical reference range used in NBRC materials. The other options either use the wrong units (L/min) or sit outside the expected upper/lower bounds (4.0 L/sec or 8.0 L/sec) for a normal, healthy individual.