Comparison of WBGTs over Different Surfaces within an Athletic Complex

Area of Science:

• Environmental Science
• Sports Medicine
• Athletic Training

Background:

• Athletic governing bodies increasingly use on-site wet-bulb globe temperature (WBGT) for heat safety.
• Microclimatic variations across different surfaces raise questions about the need for multiple WBGT sensors.

Purpose of the Study:

• To determine if WBGT readings differ significantly across common athletic surfaces (grass, artificial turf, hardcourt).
• To assess the representativeness of a single WBGT measurement for local environmental conditions in an athletic complex.

Main Methods:

• Matched WBGT data were collected every 10 minutes over four days in July 2019.
• Measurements were taken across grass, artificial turf, and hardcourt tennis surfaces at the University of Georgia.
• Data analysis considered morning, midday, and afternoon practice periods.

Main Results:

• No statistically significant differences in WBGT were found among the three athletic surfaces.
• Microclimatic differences were observed in dry-bulb and dewpoint temperatures, with higher dry-bulb and lower dewpoint over artificial turf and hardcourt.
• These temperature variations were attributed to differences in evapotranspiration and convective heat transfer.

Conclusions:

• A single WBGT monitoring site can provide representative readings for multiple athletic surfaces in humid, subtropical climates with well-watered grass.
• The counterbalancing effects of WBGT components explain the lack of surface-specific differences.
• This simplifies heat safety policy implementation for athletic organizations.