The heat index is a measurement that combines air temperature with humidity to show how hot it feels. For example, when it’s 90°F with 65% humidity, the heat index can reach 103°F. That’s especially dangerous for outdoor workers, including painters.
When the heat index gets that high, the body can’t cool itself efficiently through sweat. This increases the risk of heat exhaustion and heat stroke, both of which are medical emergencies. Signs include dizziness, nausea, headache, rapid heartbeat, and confusion.
To protect themselves, painting crews follow safety guidelines from OSHA and NIOSH. These include starting work earlier in the day, staying hydrated, taking frequent breaks in shaded or air-conditioned areas, and wearing breathable clothing.
Some job sites may also use work-rest cycles and buddy systems, especially when temperatures are extreme. A buddy system means one worker keeps an eye on another for signs of heat illness.
Being aware of the heat index isn’t just about comfort—it’s about safety and ensuring the crew can finish the job without injury or interruption.