October 22, 2009 – News
reports have surfaced detailing flash fires and explosions in livestock
buildings while liquid pit manure was being agitated and pumped.
October 22, 2009 – News
reports have surfaced detailing flash fires and explosions in livestock
buildings while liquid pit manure was being agitated and pumped.
Iowa State University
Extension agricultural engineers say these episodes highlight the caution
needed when agitating and pumping manure from pits beneath buildings.
Liquid manure in pits
undergoes slow decomposition that creates several gases including methane and
hydrogen sulfide, both of which are flammable. The rate of gas release from the
manure can be drastically increased when the manure is agitated (stirred)
during pumping. This increase is especially true for hydrogen sulfide, which
can have a lethal paralyzing effect in addition to being flammable.
To minimize risk of
injuries and flash fires, manure handlers should follow these steps:
- Review your emergency
action-plan with all workers and have emergency contact numbers available at
the site. - Prior to agitation or
pumping, turn off electrical power to any non-ventilation equipment, and
extinguish any pilot lights or other ignition sources in the building. - Fully open all ventilation
curtains or ventilation pivot-doors, but leave walk-in doors locked to prevent
human entry. - Run ventilation fans at maximum
speed. - Ensure that all people are
out of the building and clearly tag all doors noting that the building is
unsafe for entry during agitation and pumping. - Agitate the manure keeping
the jet of pressurized manure below the liquid surface. Don’t let the jet of
manure strike walls or columns in the pit. - Stop agitation when the
manure level does not allow agitation below the liquid surface. - Continue maximum
ventilation for thirty minutes after pumping has ended before re-entering the
building. - NEVER enter a building or
manure storage structure when liquid manure is being agitated or pumped.
The Iowa Pork Producers
Association has door hangtags reading “STOP Manure Agitation and Pump–Out in
Progress” available to Iowa pork producers and commercial manure applicators.
To request tags, please contact the IPPA at (515) 225-7675.
Manure gases are an
unavoidable by-product of liquid manure storage. Strict safety protocols along
with proper ventilation and agitation practices can minimize the risk of flash
fires and explosions during manure pumping.
