The downside to concerns about manure contaminating ground water is that, as manure pit storage to protect water has increased, so have fatalities due to toxic gas buildup.
Researchers estimate that about 10 people die each year in North American animal-manure pits. That doesn't sound like a lot but the number of manure storage facilities on farms is steadily growing, because the average farm size is increasing, the number of farms is decreasing and that will mean more manure pits. These deaths are entirely preventable, it was just not a problem in the past, so Penn State's College of Agricultural Sciences have published a standard for ventilation in confined animal-manure storage facilities used at large livestock operations.
Agriculture, forestry and fishing are the most dangerous occupations in the United States, with a fatality rate eight times higher than all other U.S. industries combined -- twice as great as in mining or transportation and 2.5 times greater than construction.
The benefit will be fewer multi-death accidents. Accidents typically happen when someone enters a manure pit to retrieve something, make a repair or clean the storage facility and succumb to toxic fumes caused by hydrogen sulfide, methane, carbon dioxide and other noxious gases. "When a family member comes by and sees that the father or son is in trouble, he or she goes in to try to help and is overcome," said Harvey Manbeck, distinguished professor emeritus of agricultural engineering. "Many times we have multiple deaths of family members, friends or coworkers."
In 2007, five people, including four family members, died in a manure pit at a Virginia farm. In 2012, three Pennsylvania farm-family members died in a manure-storage pond in Maryland. The new American National Standards Institute
guideline, ANSI S607, is for new or existing construction. The creators are developing an online design tool so that building professionals can create a ventilation system for any shape facility.
"What is unique is that we are making the design of a ventilation system more user friendly," Manbeck said. "And the intrinsic benefit is that if you make it easier, it increases the likelihood that such systems will be designed into new facilities or retrofitted into existing facilities."
If a building is t-shaped, for example, the online tool will evaluate how long you need to ventilate that space before the contaminate gas concentration has decreased and the oxygen level has increased to a safe level.
They estimate it will go online in 2014.
