Heat Stress

Everyone should take special precautions to avoid heat‐related illness in unusually hot weather when working outdoors or in unconditioned indoor environments. People suffer heat‐related illness when their bodies are unable to regulate internal body temperature. In hot weather, the body normally cools itself by sweating. Under some conditions, however, sweating isn’t enough. Such conditions include high humidity, where air movement is limited, working in the direct sun, heavy physical exertion and poor physical condition. Some medical conditions and medications can also reduce the body’s ability to tolerate heat. Still, heat‐related illness is preventable by following these guidelines when working outdoors in hot weather:

• Drink small amounts of cool water frequently, regardless of your activity level. Drink throughout the day.
• Replace salt and minerals. A sports beverage can replace the salt and minerals you lose in sweat.
• Wear appropriate clothing. Choose lightweight, light‐colored, loose‐fitting clothing.
• Protect yourself from the sun by wearing a wide‐brimmed hat. (Sunglasses and sunscreen—SPF 30 or higher—are also recommended.)
• Schedule outdoor work carefully. If outdoor work must be done in hot weather, try to limit it to morning hours. Limit sun exposure during mid‐day hours. Consider rotating outdoor work schedules among your co‐workers.
• Pace yourself. Start slowly and pick up the pace gradually.
• Monitor yourself for the signs and symptoms of heat‐related illness, listed below.
• Take time to cool down. Rest often in shady areas. A few hours in air conditioning can help you stay cooler later in the heat.
• Use a buddy system. When working in the heat, monitor the condition of your coworkers and have someone do the same for you.
• Monitor those at high risk. Some people are at greater risk than others, including people who are overweight, people who overexert themselves, and people with heart disease or high blood pressure, or who take certain medications.
• Take time to acclimate to heat and humidity. A heat wave is stressful to your body. You will have a greater tolerance for heat if you limit physical activity until you become accustomed to it.

Signs and symptoms of heat‐related illness include headache, dizziness, lightheadedness, fainting, weakness, mood change, mental confusion, upset stomach or vomiting. An employee experiencing the above symptoms should be taken to the UNC Hospitals emergency room as soon as possible. Contact the University Employee Occupational Health Clinic at 919-966‐9119 if you have any questions.

Departments with employees who normally work outdoors or in unconditioned indoor environments need to address heat stress in their Hazards Management Plan by including written safe job procedures appropriate to their work. Supervisors are to provide heat stress training for these employees. For assistance, please contact Environment, Health and Safety.