October 27 - The 1948 Donora Smog

Labor History in 2:00 · Oct 27, 2026 · 1m

On this day in Labor History the year was 1948.

That was the day that a thick yellow fog rolled over the town of Donora, Pennsylvania just south of Pittsburgh.

Donora was a mill town, nestled in a valley on the bank of the Monongahela River.

By 1948, the town had grown to 14,000 people, who came to work in the town’s steel mills and the Donora Zinc Works.

For years the local residents had complained about the pollution that spilled from the plants.

Smog was a regular occurrence.

But this fog was even worse than usual.

A layer of cold air was trapping a noxious blend of nitrogen dioxide…