American Farm Publications, Inc.
P.O. Box 2026
Easton, MD 21601
Deaths a reminder of safety precautions for manure pits
KENNEDYVILLE, Md. — The recent deaths of a Peach Bottom, Pa., man and two of his sons in an accident involving a manure pit are an unfortunate reminder of the inherent risks of farming and the needs for proper safety.
Glenn W. Nolt, 48, and his sons, Kelvin R., 18, and Cleason S., 14, died of asphyxia in a Kent County Farm’s 20-foot-deep manure pit.
The Office of the Chief Medical Examiner in Baltimore ruled the deaths accidental.
Nolt was a dairy farmer with 60 to 70 cows who also operated a manure-hauling business.
Nolt and his sons were working at the Maryland farm, hauling and spreading manure from the pit.
While most methods of manure handling are very efficient, they can create hazards for both humans and animals.
Ron Jester, retired Extension safety specialist for the University of Delaware, said that the hazards contained within a confined space manure storage might include a lack of oxygen, toxic and flammable gases, and exposure to drowning.
Once a person has entered a confined space manure storage, it is often too late to mitigate the associated hazards.
“Most farmers ventilate but they don’t know for sure what the gas levels are,” said Jester.
Hydrogen sulfide, one of the most dangerous manure gases, has some odor but it is often not detectable above 100 parts per million because it deadens the sense of smell.
“The gas paralyses the lungs and you are not able to breathe,” said Jester.
The gas is colorless and often can often fool even the most experienced farmer, he said.
Fatalities occur when workers enter facilities and are overcome by toxic manure gases or are exposed to an oxygen-deficient atmosphere.
According to a Penn State Extension report, 65 fatalities were reported between 1975 and 2004 across the United States when farmers, workers, family members and would-be rescuers unknowingly entered manure storages when dangerous levels of manure gas or a lack of oxygen were present. The report also showed that the rate of deaths per year in manure storages is increasing.
Several of the multiple fatality incidents involved immediate family members who lived and worked on the farm. Later reports on the incidents indicated that the initial entry into the storage was to perform work in a manner that was typical on that farm.
“People do things and they take chances,” Jester said. “They don’t think of the danger.”
To reduce the risk involved with working in and around manure pits, safety experts recommend several precautions. Portable gas detection monitors and gas detector tubes can define gas levels and sound an alarm when levels get too high.
A specially designed positive pressure mechanical forced air ventilation system can also reduce risks when entering most confined space manure storages.
This type of ventilation system forces air into the storage to replenish oxygen levels and mitigates a buildup of dangerous levels of manure gas.
“The best practice is to always ventilate,” Jester said. “You won’t see the red flags.”
It is recommended that new manure storages be designed with permanently installed positive pressure ventilation systems.
All ventilation systems should be connected to a standby power system to maintain ventilation in the event of a loss of electrical power during an entry event. The standby power system must be regularly maintained and tested.
The person entering should wear an adjustable body harness with a lifeline attached to a combined rescue and retrieval system. This person should also wear or carry a portable gas and oxygen monitor to protect against rapidly changing conditions.
A second person should be available and stationed at the entrance to the storage. This person should have the capability of using the rescue and retrieval system to lift the person out of the storage in case of emergency.
The second person should maintain either visual or verbal contact with the person in the storage. This person must also be mentally and emotionally strong enough to not enter the storage in case of emergency.
If a farm operator employs 11 or more hired workers and is inspected for any reason by the Occupational Safety and Health Administration, OSHA can cite the employer for not having the best safety practices and citations in place. This can lead to fines.
“Clean-out isn’t something that’s done too frequently,” said Jester. “If you don’t see it, you don’t think about it ... but if you’re motivated by regulations, you’ll think about it.”