The Impact of Facial Personal Protective Equipment on Speech Intensity

Importance: Facial personal protective equipment (FPPE) filters small particles in the operating room (OR) but also affects speech production, diminishing the effective transfer of information among OR team members. Objective: The aim of the study is to assess the attenuating effects of different combinations of layered FPPE on speech intensity, including potential differences in the effect of talkers with varying backgrounds and speaking volumes. Study Design: We recruited 30 speakers from health and nonhealth occupations with English as either their first or second language. All participants spoke unmasked, at varying voice levels into a portable Zoom H4n device 12 inches from the microphone. These no-mask recordings were played from a Styrofoam head, fitted with 7 combinations of FPPE commonly worn in the COVID-19 era, with the attenuated signals assessed for digital average signal levels. We submitted these attenuation values to an omnibus mixed analysis of variance and performed a spectral analysis on signal attenuation stratified by typical speech frequency bands. Results: Signal attenuation was strongly determined by FPPE combination, regardless of talker sex, first language, and occupation (P < 0.01, η 2 p = 0.881). The effects of vocal output were also significant (P < 0.01, η 2 p = 0.881). Soft talkers experienced particularly high attenuation at frequency bands higher than 2,000 Hz. The signal of the softest talkers, when asked to speak loudly, was similar to the loud talkers' signal. Conclusions: Layered FPPE in the OR protects the surgical team from small particle exposure but may increase communication failures. Our data can help OR staff choose FPPE and alter their vocal volume accordingly.