The Williams Route 66 Marathon has adopted the WBGT (Wet-Bulb Globe Temperature) index as its standard. High heat and humidity, as measured in accordance with the American College of Sports Medicine recommendations for participation in endurance events, could result in cancellation of the event. The WBGT measures the effects of heat and humidity, thereby making it more accurate than simply using the temperature alone as a gauge of conditions. WBGT is considered “the most practical heat stress index characterizing the effect of a heat stress environment on the individual.” While you might think that there’s not likely to be problem with heat during a midNovember race, the WBGT also measures when conditions are severe enough to cause hypothermia. In order to alert participants to weather conditions on race day, the Williams Route 66 Marathon will use a flag system (refer to the table below). A banner with two flags reflecting the heat stress at the start time will be suspended over the street at the starting line. Gatorade stops along the course will also fly flags corresponding to the current heat stress level. Flags will be changed within 15 minutes of a change in heat stress level. The staff manning each Gatorade stop will be familiar with the meaning of each flag color. While you personally may be used to extreme heat or cold conditions, not all participants are equally acclimated. We understand the disappointment and frustration of a race being cancelled or altered due to conditions that you personally may find acceptable. However, extreme conditions that are high risk already place a burden on community health care systems, including emergency medical transportation, as well as hospital emergency room capacity. Williams Route 66 Marathon officials will not knowingly place the community in any such position that will place a burden on the overall safety of the community. The Williams Route 66 Marathon asserts that each participant assumes responsibility when entering an event with the potential risks that endurance events present. All participants should be discerning of their own fitness level in their decision to participate in the weekend events. Furthermore, the Williams Route 66 Marathon strongly advises all participants to cooperate with directives given by Williams Route 66 Marathon officials and to assist in ensuring the safety of their fellow participants, particularly when conditions are less than ideal. Let’s make sure all participants have a fun, happy, and SAFE race day!