Manure storage can hold one of the most dangerous atmospheres on a farm, and the danger is not always something a person can see or smell, Iowa State University Extension and Outreach manure management specialist Daniel Andersen warns in a release carried by Morning Ag Clips.

"Manure is supposed to make the crop grow. It should never be the reason somebody doesn't come home," Andersen said. Four gases are commonly linked with manure storage: hydrogen sulfide, ammonia, methane and carbon dioxide. Hydrogen sulfide needs particular care, because concentrations can rise rapidly when manure is agitated or pumped, and while it smells of rotten eggs at low levels, at higher concentrations it can overwhelm and disable the sense of smell.

"Your nose is a terrible gas monitor," he said. "If you smell rotten eggs, take it seriously. If you don't smell anything, that does not mean you are safe." Research in deep-pit pig and beef buildings has recorded rapid rises in hydrogen sulfide during agitation, especially with poor ventilation. Foam on stored manure can trap methane and hydrogen sulfide, ammonia irritates eyes and lungs, and carbon dioxide can push oxygen out of low or enclosed spaces such as reception pits.

His Iowa Manure Applicator Certification programme has helped raise reported use of hydrogen sulfide detectors among Iowa applicators from less than 0.1 percent in 2018 to 7.2 percent in 2024.

The advice: never enter a manure storage or other confined manure space without the equipment, training and procedures for confined-space entry; keep people, pets and nonessential workers away during agitation and pumping; consider a properly maintained personal gas monitor; keep ventilation running and avoid sudden changes in agitation; and never attempt a rescue without proper equipment and trained responders.

"Familiarity isn't the same thing as safety," Andersen said. "Just because you agitated that pit last year and nothing happened doesn't mean the pit is safe this year."

Photo: kjkolb / Wikimedia Commons (CC BY-SA 3.0)

Source: Morning Ag Clips