Page 46
APPENDIX B
WetBulb Globe Temperature
In addition to the above race day measures, WetBulb temperature readings are monitored and recorded
every 15 minutes. These readings are applied to an environmental color coding scale (below) which is
posted at every hospitality station along the course. The color coding scale is communicated to
participants prior to the event via website and participant handbook.
WBGT Data Colour Code Risk Showers Announce
10 - 17.9 Green Low No
18 - 21.9 Yellow Moderate Optional Increasing Risk
22 - 25.9 Red High Operate Increasing Risk
26 - 27.9 Black Extreme Operate Increasing Risk
28 > Black Close Race Operate Close Race
