An exploratory study of household conditions and youth personal exposure to extreme heat during a heatwave in urban Nashville, Tennessee, USA.

Extreme heat is the deadliest meteorological hazard and is increasingly affecting the southeastern United States. Health effects of extreme heat are often not felt for hours or days after exposure and disproportionately affect vulnerable populations (e.g., youth, minorities). Personal heat exposure research has focused on occupational and everyday heat exposure among adults. To date, heat exposure in teenage populations has not been investigated. This population has unique heat exposure patterns that result from lifestyles that include outdoor jobs (e.g., lifeguard) and participation in outdoor sports. Better understanding of these exposure patterns is needed to reduce youth exposure and illnesses during heat events. Likewise, there have been no studies comparing paired indoor home conditions with individual exposure. Participants (n = 10) wore sensors to collect six days of personal heat exposure data (temperature and humidity) and placed sensors in and around their homes to collect ambient household data. When comparing individual exposure with ambient outdoor conditions and household conditions, this study revealed that: 1) teenagers are less exposed to dangerous heat (> 37.8 °C heat index) during the day; 2) teenagers are more exposed to dangerous heat (> 23.9 °C temperature) at night; 2) some teenagers are exposed to long periods of high heat at night, which is typically a time for heat recovery; and 3) household temperatures are typically not representative of heat exposure. To better understand teen exposure, we recommend future research focus on larger, representative sample sizes, collecting exposure data during the school year, and comparing exposure between heatwave and normal summer conditions.