Droplet propagation from wind instruments for different playing conditions

Droplets and aerosols are efficient agents for the airborne transmission of viruses, such as COVID-19, and musical groupings which include wind instruments must take this into account in order to minimise the risk of transmission through adequate placement of the wind players. For this reason, the dynamics of large droplets produced by playing a variety of wind instruments are examined. Playing instruments such as the flute naturally results in a steady stream of droplets propelled away from the player, whereas for other instruments the emission of droplets is heavily dependent on the register of the instrument, the articulation employed and the dynamic level at which the instruments are played. Players are filmed while playing single notes and short musical phrases corresponding to these different conditions using a high-speed camera. The trajectories of individual droplets are then mapped digitally, and the range which they cover can be estimated for each instrument. The effect of varying dynamic levels, articulation and general register of the different instruments is discussed, mainly in terms of safe placement of the instruments within an ensemble. Shock formation is also known to occur for certain brass instruments when playing loudly, and this phenomenon is expected to affect the trajectory of droplets noticeably.