Preventing Heat Illness While Working Outdoors

What Heat Illness Is & Why Heat is a Serious Jobsite Risk

The body naturally cools itself through sweating. However, when temperatures rise (especially when humidity levels are high), sweating becomes less effective as a cooling system. As a result, a worker’s body temperature can increase rapidly, leading to heat-related illness. When working outdoors, it’s important to drink water frequently and take breaks in shade or air conditioning before symptoms of heat illness begin.

Workers performing strenuous physical labor, wearing heavy PPE, or working in direct sunlight face an even greater risk of heat illness.

According to the Occupational Safety and Health Administration (OSHA), “nearly 3 out of 4 fatalities from heat illness happen during the first week of work.”

Heat illnesses can include heat cramps, heat exhaustion, or even heat stroke, a medical emergency that requires immediate attention. If you experience symptoms such as muscle spasms, heavy sweating, dizziness, fatigue, headaches, nausea, weakness, or a rapid pulse while working in the heat, it’s important to stop what you’re doing, move to a cooler location, hydrate, and monitor symptoms closely.

Warning signs of heat stroke may include confusion, loss of consciousness, seizures, slurred speech, or an extremely high body temperature. If heat stroke is suspected, call 911 and begin cooling the affected worker with water or ice while awaiting medical help and monitor symptoms.

 

How to Prevent Heat Illness

If you or your employees are working outdoors in the summer heat, take the necessary precautions to prevent heat illness:

1. Encourage frequent hydration. All workers should drink water regularly throughout the day, not just when they feel thirsty. Small amounts of water consumed frequently will more effectively keep the body temperature cool. OSHA recommends 1 cup every 20 minutes. As an employer, ensure cool drinking water is readily available at jobsites and encourage crews to hydrate throughout the day.
2. Build in rest and recovery time. Regular breaks help workers cool down and recover from heat exposure. Provide shaded or air-conditioned areas whenever possible and encourage employees to use them. As temperatures climb, additional breaks may be necessary, especially during physically demanding tasks.
3. Dress appropriately for the temperature. OSHA recommends workers “wear a hat and light-colored, loose-fitting, and breathable clothing if possible.”
4. Allow workers to acclimate. Acclimatization, the process of gradually adjusting to working in hot conditions, is crucial to preventing heat illness! New hires and employees returning after more than a week away from working outdoors should be given time to build heat tolerance through lighter workloads and increased monitoring. OSHA recommends following the “20% rule. On the first day, work no more than 20% of the shift’s duration at full intensity in the heat. Increase the duration of time at full intensity by no more than 20% a day until workers are used to working in the heat.”
5. Adjust work schedules when possible. Consider scheduling the most physically demanding work during cooler morning hours and reducing strenuous activity during peak afternoon heat. Task rotation, additional staffing, and flexible scheduling can help reduce prolonged heat exposure without sacrificing productivity.
6. Train employees to recognize warning signs. Heat illness often develops gradually, making early recognition critical. Workers and supervisors should know how to identify symptoms and understand the steps to take when someone begins showing signs of heat stress. Crew members should watch for changes in others’ behavior, coordination, and physical condition among their coworkers.
7. Remember: Water, rest, and shade. When it comes to preventing heat illness, the most effective controls are often the simplest. Access to water, opportunities to rest, and shaded recovery areas can significantly reduce the likelihood of heat-related incidents on a jobsite.

If you suspect that you or another worker is experiencing heat illness symptoms, here are steps OSHA recommends taking:

For employers, investing in heat safety is more than a compliance issue. It’s a commitment to protecting employees, maintaining productivity, and reducing the impact of preventable injuries. As temperatures rise this summer, take time to review your heat illness prevention procedures and ensure your crews are prepared to work safely in the heat.