Under new Environmental Protection Agency "good neighbor” provisions, Indiana will be required to limit pollution of nitrogen oxides in its factories. Indiana is one of 23 states whose emissions are often carried by the wind, degrading air quality in downwind states.
Nitrogen oxides are toxic to humans. It can cause problems with breathing or worsen preexisting health conditions like asthma, even in low concentrations, according to the Centers for Disease Control and Prevention. The exposure limit designated by the Occupational Safety and Health Administration is 5 parts per million for Nitrogen Dioxide and 25 parts per million for Nitrogen Oxide.
The updated regulations will focus on emissions from factories that use or produce cement, steel, iron, glass, petroleum and coal. In Indiana, regulations will affect factories as well as utility companies using coal or gas power plants.
In 2029, Indiana will have to cut nitrogen oxide pollution by over half. EPA press officer Melissa Sullivan said in a statement over email that the new regulation will improve the environment and human health across the United States.
“In 2026, EPA projects that the final rule will prevent approximately 1,300 premature deaths and avoid more than 2,300 hospital and emergency room visits, 1.3 million cases of asthma symptoms, and 430,000 school absence days,” Sullivan said.
Multiple Indiana utility companies have announced their opposition to these rules, including the Indiana Energy Association and the Indiana Municipal Power Agency. Both agencies said in replies to the regulation they believe additional regulations use incorrect data on their emissions and will negatively impact Indiana’s economy during implementation. The measure is expected to be challenged in court in the coming months.