Nitric oxide (NO) production has been described using a 2-compartment model for the synthesis and movement of NO in both the alveoli and the airways. The alveolar concentration of NO (Ca(NO)), an indirect marker of the inflammatory state of the distal portions of the lung, can be deduced through exhalation at multiple flow rates. Our objective was to determine reference values for Ca(NO). The fraction of exhaled NO (Fe(NO)) was measured in 33 healthy individuals at a rate of 50mL/s; the subjects then exhaled at 10, 30, 100, and 200mL/s to calculate Ca(NO). A chemiluminescence analyzer (NIOX Aerocrine) was used to perform the measurements. The mean (SD) Fe(NO) was 15 (6)ppb. The mean Ca(NO) was 3.04 (1.30)ppb. These values of Ca(NO) measured in healthy individuals will allow us to analyze alveolar inflammatory behavior in respiratory and systemic processes.