Physikalisch-Technische Bundesanstalt

How much air does man need for breathing? How much air can the lung take up at all? And how can a breath be described? Can breaths be compared?

A routine examination in the practice of an ENT specialist provides information about this. The state of health of the lung can be diagnosed with the aid of a spirometer which determines the volume flowrate of the exhaled air and describes it by a curve. Respiratory air volume and breath structure are impaired by illnesses, for example asthma or water in the lung. Comparable measurement results are ensured by spirometer test equipment which serves as a transfer standard and blows simulated breaths into the spirometer. This breath simulator can test the spirometer using 26 different breaths found to be typical after 3000 breaths of 600 test persons had been measured.