View of cave-in of underground Union Pacific coal mine, Rock Springs, 1930s

Underground coal mining was quite hazardous in the 19th and early 20th centuries. There were periodic cave-ins, coal dust that harmed the respiratory system, and carbon monoxide poisoning from lack of ventilation. There were also gas explosions, fires, and floods to contend with. 

Resource Identifier
Photo File: Wyoming-Rock Springs-Industries, American Heritage Center, University of Wyoming
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