Exhaled breath condensation is a non-invasive method of gathering exhaled breath samples useful for assessing a number of disease parameters. The RTube is designed to provide maximum sample collection in minimal time. Exhaled air is directed through a unique one-way valve and into a cooled collection chamber where vapors, aerosols and moisture in the breath condense along the protected inside walls of the RTube. The one way valve is then used as a plunger that collects droplets stuck to the inside wall and holds the sample near the top of the RTube.
