# Using wet-bulb globe temperature meters to examine the effect of heat on various tennis court surfaces

## TL;DR

This study used WBGT meters to compare heat levels on different tennis court surfaces, finding that hard and artificial grass courts are hotter than official weather data suggests.

## Contribution

The study provides new empirical evidence on thermal conditions specific to different tennis court surfaces.

## Key findings

- Hard courts had significantly higher WBGT at 'Warning' level or above compared to official weather data.
- Sand-filled artificial grass courts reached 'Severe Warning' levels more frequently than reported by the Japan Meteorological Agency.
- Clay courts showed the highest WBGT measurements, reaching 'Danger' levels.

## Abstract

In this study, we evaluated the thermal environments of different tennis courts using wet-bulb globe temperature (WBGT) meters. WBGT meters were installed in an outdoor hard court, sand-filled artificial grass court, and clay court (a softball field), and measurements were taken hourly from 9:00 to 17:00 on weekdays from June 1 to September 21, 2022. The results were compared with data from different courts and the nearest Japan Meteorological Agency station (JMA WBGT) based on the Japan Sports Association’s guidelines for exercise to prevent heat stroke. The median WBGT on each court was significantly higher for hard courts at the “Warning” (25 ≤ JMA WBGT < 28) level or above, sand-filled artificial grass courts at the “Severe Warning” (28 ≤ JMA WBGT < 31) level or above, and clay courts at the “Danger” (31 ≤ JMA WBGT) level than the JMA WBGT. Compared with the JMA WBGT, hard and sand-filled artificial grass courts are played on under particularly hot conditions. The results of this study could indicate to tournament organizers and coaches the importance of measuring the WBGT on each court surface from an early stage to prevent heat-related incidents.