Assistant Professor of Public Policy R. Jisung Park spoke to NBC News about the high risks of illness and injury associated with working in hot environments. As temperatures rise across the country, essential workers face increased risk of heat illness, a common problem for delivery workers that has been exacerbated by the pandemic. An increase in the volume of packages being sent during the pandemic has stepped up pressure on delivery workers to work harder and avoid taking breaks. Many delivery vehicles and warehouses are not air-conditioned, and mandating masks can make it more difficult for the body to cool down. Experts have found that high temperatures can have devastating effects on the body. “Heat illnesses, heat cramps — these can be deadly,” Park said. “But there’s evidence that finds that hotter temperatures raise the risk of other injuries, too,” with instances of fatigue or fainting sometimes leading to organ failure.