Understanding Airborne Spread: Insights from Everyday Behaviors and Physiological Factors

Researchers at Clarkson University researchers have shown that behavioral and physiological factors—particularly volume, age, and hydration—significantly influence aerosol emissions during everyday activities, with clear implications for indoor airborne exposure risk.

They measured aerosol generation during routine behaviors, including breathing, speaking, and singing, with varying vocal intensity and pitch across age groups. Particle counts were the primary endpoint.

Louder and higher-pitched vocalization consistently raised particle emission. Elevated speaking volume and pitch produced measurable increases in aerosol counts, leading the researchers to identify speech volume as a modifiable source-strength risk factor.

Age and hydration further modified emissions. Older adults produced higher aerosol counts than children and teens, and changes in fluid balance were associated with differences in particle output.