Last October, Humberto “Antonio” Padua Hernandez was loading pig manure into tanker trucks to be used as fertilizer. From the top of the tanker, the 32-year-old worker with Ohio-based W.E. Soil Enhancement was pumping manure from the building to the tank.

It’s unlikely Hernandez smelled hydrogen sulfide’s infamous rotten-egg smell. The gas causes “olfactory fatigue,” which deadens the ability to smell looming danger. The gas quickly overcame him, leading to his death.

Following an investigation by the U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA), W.E. Soil Enhancement is facing penalties and serious violations.

OSHA told PORK Network, “The agency has standards in place that require employers to educate employees on chemical hazards, assess respiratory hazards and maintain hazardous chemicals below the permissible exposure level; had these standards been followed it is highly likely that a fatality would not have occurred.”

OSHA cited W.E. Soil Enhancement with numerous serious violations, proposing penalties of $16,800.

On page nine of the report, OSHA demands W.E. Soil Enhancement:

  • Use an appropriate truck for manure and sewage removal. OSHA said a closed, vacuum pumping system would have prevented the open-air release of hydrogen sulfide, while a gauge on the outside of the tank would have enabled Hernandez to monitor the fill line from the ground rather than from the top.
  • Prohibit access to the hatch of the tank during pumping and agitation of the manure.
  • Establish a “no personnel” zone around and on top of the tank while manure is being pumped or agitated. 
  • Implement a set amount of time before workers can re-enter the “no personnel” zone after the pumping has stopped
  • Train all employees who work with manure on the hazards of hydrogen sulfide. In addition, employees should have a self-contained breathing apparatus if accessing an area where hydrogen sulfide or other toxic gases would be present whenever manure is agitated and wear a hydrogen sulfide monitor during manure removal.

Click here for the full 13-page report.

Rich Eshleman, part-owner of W.E. Soil Enhancement, described the incident as a “freak accident” but told Farm and Dairy he doesn’t feel the company did anything wrong. His company plans to appeal the fines.

“I’ve been in the exact same position,” Eshleman said of Hernandez, who was outside and in open air as he worked on top of the tank. “I can’t figure it out.”

However, Dr. Renée Anthony with the Great Plains Center for Agricultural Health explained to PORK Network the importance of keeping employees off of the tank during pumping.

No one should be on top of an open tank when it is being filled with manure or other materials that could release hydrogen sulfide,” she stressed.

Anthony urges employers to purchase direct-reading monitors to notify workers of serious risks in real-time, especially because “olfactory fatigue” prevents workers from detecting dangerous levels of hydrogen sulfide.

“Because concentrations rise quickly when handling manure, these monitors should be set to alarm at levels well below the lethal concentrations so that workers have time to react and leave the area before the concentration becomes deadly,” Anthony said. “These small, inexpensive ($100-200) monitors can be worn by everyone involved in the pumping operation:  when these monitors alarm, they alert individuals to leave the area. The monitor then serves to indicate whether they have left to a safe area.”

The bottom-line: employers must keep their workers safe from hydrogen sulfide.

As OSHA said, “Ultimately [employers] are responsible to determine how their employees can be exposed to this toxic gas, how they are going to protect their employees from this toxic gas, and train the employees about the hazards of hydrogen sulfide and protective measures that will be used to keep them safe. “