Infrared measurement of carbon dioxide in the human breath: Breathe-Through devices from Tyndall to the present day

The ability to measure carbon dioxide (CO(2)) in the breath of a patient or capnometry, is one of the fundamental technological advances of modern medicine. I will chronicle the evolution and commercialization of mainstream capnometry based upon infrared measurement of CO(2) ill the breath using information from the historical record and personal interviews with many of the developers.