Barns, silos, sheds, and other farm buildings can be cause for concern when used to store feed, manure, animal bedding, and hazardous chemicals. When damp hay is stored in warm barns, molds can grow. These molds can cause respiratory problems, allergies, and asthma. Repeated exposure to molds can cause “farmer’s lung,” an allergic inflammation of the lungs that can become life-threatening.
Poorly ventilated barns can compound the air quality and dust problems created by moving, handling, or feeding animals. Exposure to high levels of organic dust can cause Organic Dust Toxicity Syndrome, which causes cough, fever, chills, and muscle pain.
Some barns store animal manure in a pit located directly below the floor where animals are kept. This is the most dangerous way to store manure and these pits can emit potentially deadly gases: ammonia, carbon dioxide, hydrogen sulfide, and methane. As manure decays and ferments, it creates these gases and can cause death, oxygen depletion, asphyxiation, and toxic reactions in people or animals. The gases can also cause explosions when stored in a closed area.
Dangerous silo gases can form with the natural fermentation of hay or other crops shortly after they are placed in the silo. These gases can include nitrogen dioxide and carbon dioxide, which are both odorless and colorless. A farmer can be exposed to silo gas but not know it. Exposure to high concentrations of nitrogen dioxide gas can cause fluid to collect in the lungs, and even cause death.
Farm buildings are often used as catch-all storage places for products used around the property like fertilizer, pesticides, solvents, cleaning products, herbicides, paints and paint thinners, and lubricants. Many of these products include hazardous ingredients and require safe handling and storage. Farm buildings are at increased fire risk because stored farm chemicals, along with hay, straw and other bedding, can easily catch on fire. Some stored products, such as gasoline, kerosene, oil, and aerosol cans, can even increase the speed at which a fire spreads.
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