  In the midst of the COVID-19 pandemic, many live musical activities had to be
postponed and even canceled to protect musicians and audience. Orchestral
ensembles face a particular challenge of contamination because they are
personnel heavy and instrumentally diverse. A chief concern is whether wind
instruments are vectors of contamination through aerosol dispersion. This
study, made possible by the participation of members of the Philadelphia
Orchestra, brings insight on the modes of production and early life of aerosols
of human origin emitted by wind instruments. We find that these instruments
produce aerosol levels that are comparable to normal speech in quantity and
size distribution. However, the exit jet flow speeds are much lower than
violent expiratory events (coughing, sneezing). For most wind instruments, the
flow decays to background indoor-air levels at approximately 2 meters away from
the instrument's opening. Long range aerosol dispersion is thus via ambient air
currents.
