Managing Heat on the Farm

As we get through the last days of June and turn the calendar to July, OSU Extension State Climatologist, Aaron Wilson has expressed concern for both human and livestock welfare as we enter our first major heat wave of the season. With forecast highs in the mid to upper 90s and humidity levels climbing, heat index values will likely be well over 100°F in the coming days.  Add this to little cooling in the evenings later this week, steps will need to be taken to ensure everyone stays cool and safe.

Looking at the numbers:

• Originally issued in April 2022 and revised in April 2026, the Occupational Safety and Health Administration (OSHA), under the Department of Labor, updated the framework that addresses heightened efforts to keep workers safe in the heat.  This particularly focuses on dangers to agricultural workers.  Since 2022, OSHA has conducted over 7,000 inspections that were heat related. This is a large increase from 200 inspections annually prior to 2022. 
• A study using the Census of Fatal Occupational Injuries database found that heat-related deaths are 35 times higher in farm workers when compared to workers in other industries. 
• Ohio State University researchers have estimated that economic loss to the United States livestock and poultry industries due to heat stress can range from $1.9 to $2.7 billion annually.

Keeping an eye on the weather forecast is the first step in prevention.  Much attention is paid to tornadoes, severe storms, and floods. However, according to the National Weather Service, heat related deaths are still the greatest weather-related cause of death in the U.S.

 

Heat advisories and extreme heat warnings are both based on the heat index which is a combination of air temperature and humidity. 

• Extreme Heat Warning is issued when the heat index is expected to reach 105°F or higher for a period of at least 2 hours. A warning would also be appropriate if heat advisory criteria are expected to be reached for 4 consecutive days.
• Extreme Heat Watch is issued when there is potential for heat index values of 105°F or hotter within the next 24 to 48 hours.
• Heat Advisories are issued for heat index of equal to 100°F and less than 105°F for a period of at least 2 hours.

The NWS also provides a Heat Risk Tool that provides a 7-day forecast of the potential level of risk for heat-related impacts (https://www.wpc.ncep.noaa.gov/heatrisk/).

 

Heat exhaustion and heat stroke are real possibilities with indices this high while also possible at lower levels depending on the health of the individual.

Here are some best management practices to keep you and your livestock more comfortable:

Farmers and employees:

1. Start the day well hydrated and keep drinking water regularly through the day.  If you wait until you are thirsty, you have waited too long.
2. Keep particularly strenuous tasks (especially those requiring additional personal protective equipment) to the cooler parts of the day when possible.
3. Increase number of breaks and slowly build up a tolerance to working in the heat, especially in the first few high heat events in the season

Livestock:

1. Ensure all ventilation equipment in barns is well maintained and functioning properly.  If temperature alarms are present, test them.
2. Always have fresh, clean water available to the animals.
3. Shade must be available for animals not confined in structures.
4. Consider changing feeding times for animals.  Feed intake produces heat.  This usually peaks 4 to 6 hours after feeding.  Receiving more of the daily ration after the heat of the day will help relieve some of this added stress.

Prevention of heat-related illness is ideal, but awareness of the signs to watch for is also important to be prepared for action.  According to OSHA, heat exhaustion symptoms include fatigue, irritability, thirst, nausea, dizziness, heavy sweating, and elevated body temperature or fast heart rate.  If you or someone you are with is experiencing these symptoms, move to a cooler area and cool the body by loosening clothing, drinking water, fanning, or using cool, wet towels.  If symptoms persist, seek medical attention.

Heat stroke is the most serious of heat-related illnesses.  Regardless of age, over 20% of those suffering from heat stroke will die.  In addition to the symptoms of heat exhaustion, a heat stroke victim will also show signs of confusion, slurred speech, unconsciousness, seizures, or hot, dry skin. If these additional symptoms are observed, take same action as heat exhaustion, and dial 911 immediately.

Wayne Dellinger, ANR Educator Union County, can be reached at 937-644-8117 or dellinger.6@osu.edu. Aaron Wilson, Ag Weather and Climate Field Specialist, can be reached at 614-292-7930 or wilson.1010@osu.edu.  This column is provided by the OSU Extension Agricultural Safety and Health Team. https://agsafety.osu.edu/.