Effects of surgical masks on aerosol dispersion in professional singing

Background In the CoVID-19 pandemic, singing came into focus as a high-risk activity for the infection with airborne viruses and was therefore forbidden by many governmental administrations. Objective The aim of this study is to investigate the effectiveness of surgical masks regarding the spatial and temporal dispersion of aerosol and droplets during professional singing. Methods Ten professional singers performed a passage of the Ludwig van Beethoven’s “Ode of Joy” in two experimental setups—each with and without surgical masks. First, they sang with previously inhaled vapor of e-cigarettes. The emitted cloud was recorded by three cameras to measure its dispersion dynamics. Secondly, the naturally expelled larger droplets were illuminated by a laser light sheet and recorded by a high-speed camera. Results The exhaled vapor aerosols were decelerated and deflected by the mask and stayed in the singer’s near-field around and above their heads. In contrast, without mask, the aerosols spread widely reaching distances up to 1.3 m. The larger droplets were reduced by up to 86% with a surgical mask worn. Significance The study shows that surgical masks display an effective tool to reduce the range of aerosol dispersion during singing. In combination with an appropriate aeration strategy for aerosol removal, choir singers could be positioned in a more compact assembly without contaminating neighboring singers all singers.

Correlations between oropharyngeal and laryngeal anatomy and the frequency of singing voice: A population-based study, in Greece

The aim of this study is to explore if there is correlation between the typical voice classification and oropharyngeal anatomy, using cervical posterior-anterior radiography on professional singers in Epirus, Greece. Methods: 70 professional singers, 35 men and 35 women, were recruited for this study. All participants underwent a cervical posterior-anterior radiographic imaging of their oral pharyngeal and laryngeal area. Results: A statistically significant difference of mean distance was observed for the CI-MHP area (p=0,004), the MHP- SCV area (F=2,62, p=0,032), as well as SCV-AI area (F=11,82, p=0,000). For the average length measured in mm of the phonetic area PA, statistically significant differences were computed among all the singers in the group (F [5] = 5.368, p = 0.001), as well as the OPC area (F = 6,48, p = 0,000). Conclusions: The cervical posteroanterior radiography provided new correlations of the voice category of professional singers with their Oropharyngeal and Laryngeal Anatomy.

Madrigals, Part 5

Marco da Gagliano's Quinto libro de madrigali a cinque voci was published in October 1608, a little less than two years after his previous book. It contains fourteen madrigals for five voices and one for seven, all composed by Gagliano. The poets represented include Giambattista Marino, Giovanbattista Strozzi, both the older and the younger, Cosimo Galletti, and Ottavio Rinuccini. The madrigals of book 5 are quite varied in their style and their treatment of text. Many are light and remarkably concise, like the canzonetta-influenced madrigals of the Quarto libro, and most often set text syllabically to shorter rhythmic values in motives that alternate between homophony (or near homophony) and polyphony, imitative or nonimitative. Some, however, set poetry very differently. A three-part setting of a Marino sonnet, for instance, is filled with virtuoso melisma, probably intended for the professional singers of the Medici court. Book 5 also includes a concertato madrigal for seven singers and basso continuo that bears the prescriptive direction “per cantare e sonare” (for voices and instruments) in the basso partbook. Although there is no notational indication of instruments, the basso part lacks text for several measures, and it is likely that it was performed with improvised chords on an instrument. The book also contains two threnodies for Count Cammillo della Gheradesca that are in a somber and more traditional polyphony and contrast with the rest of the book's contents.

A highly efficient cloth facemask

Wearing masks and face coverings helps reduce transmission of respiratory diseases. Much prior research on mask filtration efficiency has focused on fabric type, with less consideration given to mask design and shape. Here, we present evidence that increasing the mouth-mask separation distance engenders an increase in the mask-fabric filtration efficiency towards expiratory aerosols emitted via vocalization, which we attribute to a decrease in the expiratory jet velocity and expansion of the breath-mask contact area. We further assess the performance of a new reusable cloth facemask design, originally made for, but not exclusive to, professional singers and having a large mouth-mask separation distance. With proper fitting, these masks achieve overall filtering efficiencies of >93% for both exhaled expiratory aerosols >0.5 microns in diameter from singing and speaking and for inhaled ambient aerosols, better than surgical masks and approaching N95 respirators. Air exchange between the mask deadspace and the ambient environment limits the extent of CO2 buildup and in inhaled air and maintains O2 levels near ambient. The mask design also provides for less inhibited mouth and jaw movement and lower relative humidity, suggesting it may provide a more palatable, high-efficiency alternative to medical-grade masks for the public.

The effect of singers masks on the impulse dispersion of aerosols during singing

Background: During the Covid-19 pandemic, singing activities were restricted due to several super-spreading events which have been observed during rehearsals and vocal performances. However, it has not been clarified how the aerosol dispersion, which has been assumed to be the leading transmission factor, could be reduced by masks which are specially designed for singers. Material and Methods: 12 professional singers (10 of the Bavarian Radio-Chorus and two freelancers, 7 females and 5 males) were asked to sing the melody of the ode of joy of Beethovens 9. symphony Freude schoener Goetterfunken, Tochter aus Elysium in D-major without masks and afterwards with five different singers masks, all distinctive in their material and proportions. Every task was conducted after inhaling the basic liquid from an e-cigarette. The aerosol dispersion was recorded by three high-definition video cameras during and after the task. The cloud was segmented and the dispersion was analyzed for all three spatial dimensions. Further, the subjects were asked to rate the practicability of wearing the tested masks during singing activities using a questionnaire. Results: Concerning the median distances of dispersion, all masks were able to decrease the impulse dispersion of the aerosols to the front. In contrast, the dispersion to the sides and to the top was increased. The evaluation revealed that most of the subjects would reject performing a concert with any of the masks. Conclusion: Although, the results exhibit that the tested masks could be able to reduce the radius of aerosol expulsion for virus-laden aerosol particles, there are more improvements necessary to enable the practical implementations for professional singing.

Aerosol emission in professional singing of classical music

In this study, emission rates of aerosols emitted by professional singers were measured with a laser particle counter under cleanroom conditions. The emission rates during singing varied between 753 and 6093 particles/sec with a median of 1537 particles/sec. Emission rates for singing were compared with data for breathing and speaking. Significantly higher emission rates were found for singing. The emission enhancements between singing and speaking were between 4.0 and 99.5 with a median of 17.4, largely due to higher sound pressure levels when singing. Further, significant effects of vocal loudness were found, whereas there were no significant differences between the investigated voice classifications. The present study supports the efforts to improve the risk management in cases of possible aerogenic virus transmission, especially for choir singing.

An improved and highly efficient geometry for facemasks

Wearing masks and face coverings helps reduce transmission of respiratory diseases. Much prior research on mask filtration efficiency has focused on fabric type, with little consideration given to mask geometry. Here, we present evidence that increasing the mouth-mask separation distance engenders an increase in the mask-fabric filtration efficiency towards expiratory aerosols emitted via vocalization, which we attribute to a decrease in the expiratory jet velocity. We further assess the performance of a new reusable cloth facemask design, originally made for professional singers and having a large mouth-mask separation distance. With proper fitting, these masks achieve overall filtering efficiencies of >93% for both exhaled expiratory aerosols from singing and speaking and for inhaled ambient aerosols, better than surgical masks and approaching N95 respirators. The mask design also provides for less inhibited mouth and jaw movement, suggesting it may provide a more palatable, high-efficiency alternative to medical-grade masks for the public.

A survey of vocal health in church choir singers

Purpose Choir singing is an important tradition of Christian worship across India. However, vocal health issues related to the church choir singers are less addressed in the literature. Hence, this study aimed to investigate the prevalence of vocal symptoms, identify the variables associated with increased risk of voice problems and knowledge of factors influencing vocal health in church choir singers. Method One hundred and forty-eight church choir singers (61 males and 85 females) between the age range of 18 and 70 years participated in the study. They completed a self-reported questionnaire addressing demographic and singing-related details, vocal symptoms, variables associated with increased risk reporting voice problems and knowledge about factors influencing vocal health. Result Eighty-four percent of the choir singers reported two or more vocal symptoms sometimes or more frequently while or after singing. More than half of the church choir singers had experienced vocal symptoms such as accessing notes in the upper range, loss of vocal endurance, pitch breaks, hoarseness, dryness in the throat, and discomfort in the throat. Among the different variables, systemic hydration found to have a significant association with reporting of voice problems in church choir singers. The overall knowledge regarding the factors influencing vocal health was found to be limited among the choir singers. Conclusion Choir singers like other professional singers experienced a higher prevalence of vocal symptoms during or after singing and exhibited limited knowledge about factors that negatively influence vocal health. Hence, there is a need to look into these singer’s vocal requirements, who usually go unnoticed.