At a building construction site near downtown Bloomington, outdoor workers continued to do their job even in scorching heat. Allen Rouse, a union electrician, looked at his watch to check how long before his shift ends. He said they try to stay cool throughout the day.
“In order to beat the heat, we just bring coolers with us and fill it up with ice and make sure we get plenty of water,” he said while carrying a load of electric wiring frames on his shoulder.
“We just drink plenty of water throughout the day.” He also puts a wet towel on his neck just to stay cool.
Extreme heat can cause health risks to outdoor workers, people with underlying health conditions, elderly people, children and people without or with limited cooling access.
In urban areas, extreme heat days can cause heat island effects, which makes urban neighborhoods hotter than others.
Urban heat island effect
The urban heat island occurs because more heat is stored in urban buildings primarily because of cement structures and lack of green infrastructure, such as trees, grass and open areas.
Zachary Schlader, associate professor at the IU School of Public Health, researches the implications of thermal stress, including heat and humidity, on human health.
He said heat may bring physiological responses, such as sweating, heart rate increase and red skin. “In most healthy people, this is just a normal physiological response, but in certain at-risk populations, that normal response could tip towards a pathological response or a negative health outcome response,” he said.
“Given the urban heat island, typically a lot of at-risk populations are in urban settings. Because of those two things, there is a heightened risk of bad health outcomes with the urban heat island.”
According to the Indiana climate change impacts assessment, the number of extreme heat events will continue to rise in all areas of the state. It projected that these events will triple by the 2050s. The number of extreme heat events per year will rise to nearly 90 by then.
Last summer the City of Bloomington did heat mapping to create an urban heat island map. Downtown was among the hottest parts of the city. Urban heat islands in Bloomington are projected to expand significantly.
Compared to rural areas with farmland and places with forest, urban settings get more heat in the same weather. Schlader said the urban area is not only hotter during the day, but also at night.
“That's because all of these structures soak up heat, and they hold the heat in so that at nighttime, it ends up being warmer there than it would be in other locations,” he said.
Heat needs to be taken seriously
Extreme heat may increase the risk of heat stroke, cardiovascular disease, respiratory disease; it is also associated with increased hospital admissions for kidney and respiratory disorders, according to the Centers for Disease Control and Prevention .
Public health experts say heat needs to be taken seriously and that a support system should include heat advisories and cooling opportunities to help protect people, particularly those who are likely unable to escape the heat.
“I think just raising the awareness of heat as a natural disaster, and that has a very big impact on human health, is really important,” Schlader said.
As of May 2025, nearly 50% of Americans are at least “moderately worried” that their local area might be harmed by extreme heat, according to research from the Yale Program on Climate Change Communication.
In Bloomington, outdoor workers like Rouse are trying to cool themselves while working on hot summer days.
“Make sure you take plenty of breaks after you do a bunch of work. Make sure you take at least 15 minutes, 20 minutes just to relax and not pretty much work yourself to death,” he said.