“Cow-pies” in the field pose no particular danger. Manure in large quantities contained in storage facilities such as vats or below ground pits can prove to be fatal. Cases have been documented where several individuals have died while attempting to rescue other people that have succumbed to asphyxiation in a pit. Anyone visiting or working on a farm that handles livestock waste, should be aware of the dangers associated with manure storage and take the necessary precautions to avoid injury or death.
Manure is a necessary by-product of raising animals and has long served as fertilizer. Research is aimed at converting manure by-products into alternative fuel sources indicating that storage facilities may be on the rise.
Through decomposition, manure creates gases such as hydrogen sulfide, carbon dioxide, ammonia and methane. When accumulated in high concentrations, these gases are toxic and in the case of methane, it can be explosive. According to the Farm Safety Association, hydrogen sulfide is considered the most dangerous of the by-products. It has a rotten-egg smell that can no longer be detected after breathing the gas in for a short period of time. At low concentrations it irritates the eyes and respiratory tract. At moderate levels, exposure causes headache, nausea and dizziness. At high levels, hydrogen sulfide, as well as carbon dioxide and ammonia can cause unconsciousness, respiratory failure and death.
Gas build up is more prevalent in confined areas but regardless of the type of storage, when manure is disturbed (e.g. pumping) the risk of gas release is at its highest.
- Keep unnecessary personnel, children and livestock away from the work in progress and maximize ventilation.
- Do not smoke and remove sources of open flame or sparks including fuel-fired heaters. It is recommended that heaters be installed on the outside of the building.
- Eliminate the need for entry into the pit by providing access to all serviceable parts from the outside. If you must enter the area, recognize that the risk is greatest when the manure is agitated, increasing the release of dangerous gases. You must test the oxygen level and gas concentrations before entering and wear a self-contained air supply (not a dust-mask). Wear a body harness and a safety line and never work alone.
Remember… if someone has collapsed in a pit, it may be due to toxic gas and it is suicidal to enter without proper breathing apparatus. Without the right equipment, you will not be able to help.
Most deaths occur during the summer months, a time when many agricultural producers are emptying pits. Regardless of the season, it is always best to presume that the pit contains hazardous gases or lacks oxygen. Take the measures necessary to protect yourself and get the air that you need to breathe while working in or around the pit.
