Heat related illness (HRI) can happen any time of year in our Florida environment. Gardeners and outdoor enthusiasts are most at risk for exposure when the heat index is high. The heat index is what the temperature feels like to the human body when the air temperature is combined with relative humidity. It is considered dangerous when it is 90 degrees or higher. Heat index is measured according to the temperature in the shade; direct sunlight can increase the heat index by up to 15%. The heat index is available on weather apps and channels.
Here are some examples to explain how heat index is measured:
85 degree temperature with 60% humidity results in a heat index of 90 degrees.
84 degree temperature with 70% humidity results in a heat index of 90 degrees.
90 degree temperature with 40% humidity results in a heat index of 90 degrees.
Understanding why the heat index is important can help gardeners make wiser decisions about when we choose to garden (or not!).
Our bodies are designed to help regulate our internal temperatures; however, certain factors can interfere with our bodies ability to self-regulate. When we get too hot, we start to perspire, which helps us cool off when the sweat evaporates. When the sweat is not able to evaporate, due to high humidity, our bodies lose the ability to regulate and heat gets trapped inside our bodies. This is when we become at risk for heat related illnesses, such as heat exhaustion or heat stroke.
To prevent heat related illnesses, take precautions such as checking the heat index before gardening, and gardening in the morning or evening instead of daytime. Protect your skin from the sun by wearing light-weight and light-colored clothing, and a wide-brimmed hat to protect your skin from harmful UVA and UVB rays. Wear sunscreen and reapply regularly. Drink at least 8 to 12 ounces of water, juice, or electrolyte drink before going outside to garden, and drink at least that much every hour you are outside, even if you do not feel thirsty. Take frequent breaks in the shade – at least every 15 to 20 minutes.
It is important to understand the symptoms of heat exhaustion or heat stroke so you can take immediate measures. Heat exhaustion is characterized by feeling faint or dizzy; sweating excessively; having cool, pale, or clammy skin; nausea or vomiting; and/or a rapid, weak pulse. If you start to experience any of these symptoms, immediately go to a cool, shady location and drink cool fluid. Remove some of your clothing and cool your body by wetting your skin with cool towels.
If you do not improve, seek medical attention. Symptoms of heat stroke include confusion; headache; red, hot, dry skin; nausea or vomiting; body temperature above 103 degrees; rapid pulse; and/or loss of consciousness. Heat stroke is a medical emergency, and 911 should be called immediately.
Armed with proper information and the foresight to take preventative measures to reduce your risk of a heat-related illness, gardening in Florida can be a healthy, therapeutic, and bountiful hobby.