Hydrogen sulfide can cause nearly-instant death at high concentrations.

At lower levels, it can result in swift loss of consciousness, pulmonary edema, and decreased oxygen supply to the brain.

Hydrogen Sulfide Safety - Iowa Manure Management Action Group

The Manure Scoop - Iowa State University Extension

Reoccurring Themes of Manure Gas Deaths - PennState Extension

Manure Gases - Great Plains Center for Agricultural Health

Fact Sheet: Safe Manure Removal Policies - National Pork Board

ATV Safety Institute

ATVCourse.com Educating Riders Online

New Engineering Safety Devices for All-Terrain Vehicles - Dee Jepsen, Ohio State University Extension

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