Résumé
Opera singers are known for their ability to control their respiration and exhalations during a musical performance. However, air flows exhaled by singers were questioned during the COVID-19 pandemic as clusters of infections were identified within choirs due to the release of pathogenic droplets during rehearsals. Indeed, singing leads to an increased number of aerosol droplets released by a person. The expiratory air flows from a singer are of interest as there is a possibility of contaminated droplets to be transported by the exhaled air.We observed the air exhaled by a mezzosoprano singer during her performance of an Armenian lullaby “Oror.” We use a high-speed infrared camera (FLIR X6900SC) operating in the midwave range of the infrared spectrum (1.5–5 μm). The use of a filter in the absorption range of CO2 (4.2 μm) enables tracking the warm exhaled CO2. The opera singer sat beside a dark nonreflective curtain that provided a uniform background at the ambient temperature. As seen in the image sequence of Fig. 1, the infrared imaging captures the warm face of the singer and the warm exhaled CO2. The spatial extent of the exhaled CO2 can, thus, be estimated.