Exhaled respiratory particles during singing and talking

• Choir singing has been suspended in many countriesduring the Covid-19 pandemic due to incidental reportsof disease transmission. The mode of transmission has been attributed to exhaled droplets, but with the exception of a study on tuberculosis from1968, there is presently almost no scientific evidence ofincreased particle emissions from singing. A substantial number of studies have,however, investigated aerosols emitted from breathing,talking, coughing and sneezing. It has also been shown that justnormal breathing over time can generate more viablevirus aerosol than coughing, since the latter is a less fre-quent activity.Compared to talking, singing often involves continu-ous voicing, higher sound pressure, higher frequencies,deeper breaths, higher peak airflows and more articu-lated consonants. All these factors are likely to increaseexhaled emissions.The aim of this study was to investigate aerosol anddroplet emissions during singing, as compared to talking and breathing. We also examined the presence of SARS-CoV-2 in the air from breathing, talking and singing,and the efficacy of face masks to reduce emissions. In this study we defined aerosol particles as having a drysize in the range 0.5–10mm. Although debatable from anaerosol physics point of view, a cutoff diameter between5 and 10mm is normally used in medicine for classifica-tion of aerosol versus droplet route of transmission. Droplets are here defined as exhaled particles, frommicron size with no upper size limit, and measured dir-ectly at the mouth before complete evaporation, thuspartly in liquid phase.

• Choir singing has been suspended in many countries during the Covid-19 pandemic due to incidental reports of disease transmission (Hamner et al. Citation2020). The mode of transmission has been attributed to exhaled droplets, but with the exception of a study on tuberculosis from 1968, there is presently almost no scientific evidence of increased particle emissions from singing (Loudon and Roberts Citation1968). A substantial number of studies have, however, investigated aerosols emitted from breathing, talking, coughing and sneezing (e.g., Asadi et al. Citation2019; Johnson et al. Citation2011). It has also been shown that just normal breathing over time can generate more viable virus aerosol than coughing, since the latter is a less frequent activity (Lindsley et al. Citation2016).Compared to talking, singing often involves continuous voicing, higher sound pressure, higher frequencies, deeper breaths, higher peak airflows and more articulated consonants. All these factors are likely to increase exhaled emissions.The aim of this study was to investigate aerosol and droplet emissions during singing, as compared to talking and breathing. We also examined the presence of SARS-CoV-2 in the air from breathing, talking and singing, and the efficacy of face masks to reduce emissions. In this study we defined aerosol particles as having a dry size in the range 0.5–10 µm. Although debatable from an aerosol physics point of view, a cutoff diameter between 5 and 10 µm is normally used in medicine for classification of aerosol versus droplet route of transmission. Droplets are here defined as exhaled particles, from micron size with no upper size limit, and measured directly at the mouth before complete evaporation, thus partly in liquid phase.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Hälsovetenskap -- Folkhälsovetenskap, global hälsa, socialmedicin och epidemiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Health Sciences -- Public Health, Global Health, Social Medicine and Epidemiology (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Annan teknik -- Övrig annan teknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Other Engineering and Technologies -- Other Engineering and Technologies not elsewhere specified (hsv//eng)

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Meteorologi och atmosfärforskning (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Meteorology and Atmospheric Sciences (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Oto-rhino-laryngologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Otorhinolaryngology (hsv//eng)

Keyword

Covid-19

Singing

Talking

Disease transmission

Publication and Content Type

art (subject category)

ref (subject category)