The hours between 9 p.m. and midnight on July 4, 2021, ranked as the most intensely polluted hours the city experienced at any point over the past year, according to analysis of data on Chicago’s air quality. The new analysis is part of an ongoing project about air quality by MuckRock, WBEZ and the Sun-Times.

Estamos también buscando voluntarios para instalar sensores de calidad del aire en el exterior de sus casas. Si está interesado, complete el formulario más abajo.

Local newsrooms are collaborating to measure air pollution in Chicago and nearby suburbs. And we need your help.

Fine particulate matter is responsible for an estimated 5% of all premature deaths in Chicago. What is it and where does it come from?

Chicago’s air pollution hotspots: New sensor network reveals neighborhood air quality disparities