A Proactive Approach to Heat Illness

April 07, 2011

Robin Whisman
Assistant Director for Injury Prevention and Care
Campus Recreation
University of Nebraska, Lincoln

Heat illness poses a serious risk to individuals engaging in physical activity, especially when exercising outdoors or in facilities that are not climate-controlled. Unfortunately, people are often unaware that they are at risk for heat illness until it is too late. Even in less-than-scorching heat, high humidity levels can impair the body’s ability to cool itself. At the University of Nebraska-Lincoln, Campus Recreation has adopted a proactive approach to dealing with heat illness that involves monitoring conditions, educating patrons, and closing facilities if conditions become hazardous.

To help reduce our patrons’ risk of suffering from heat illness, we monitor the temperature in our non-climate-controlled indoor facilities by using wet bulb globe thermometer (WBGT) readings from a digital sling psychrometer. During the warmest part of the year (mid-May through the end of August), readings are taken four times per day (mid-morning, noon, mid-afternoon, and early evening) whenever the outside temperature reaches over 80ï‚°F.

The following table, adapted from the consensus statement issued by the Inter-Association Task Force on Exertional Heat Illness, is used to determine the level of risk and the corresponding flag (or color-coded marker) is displayed. If conditions in any of the monitored areas reach the “black” zone, that area is closed until conditions improve. WBGT readings are repeated every 30 minutes in a closed area, and the area is reopened when conditions are no longer in the “black” zone. This policy applies only to our non-climate-controlled indoor facilities.

WBGT Reading      Flag Color      Level or Risk      Comments
<65° F                    Green               Low              Risk low but still exists
65°-73°F                 Yellow           Moderate          Risk level increases through the day
73°-82°F                 Red                   High            Individuals at risk should not compete
>82°F                     Black              Extreme         High Alert*

*Consider rescheduling or delaying the event until safer conditions prevail; if the event must take place be on high alert. Take steps to reduce risk factors (e.g., more and longer rest breaks, reduced practice time, reduced exercise intensity, access to shade, minimal clothing and equipment, etc).

In addition to the large signs that display the color-coded markers representing the current risk level, we also have heat illness info cards available for patrons. These cards contain heat illness prevention tips and general information about the symptoms and treatment of heat illnesses (including heat cramps, heat exhaustion, and heat stroke), as well as our heat illness prevention policy and the table shown above.

For more information on exertional heat illness, see the National Athletic Trainers’ Association Position Statement: Exertional Heat Illnesses (Journal of Athletic Training 2002; 37(3):329—343).