You know the importance of farm safety, and you are adamant that your farm staff, spouse and family follow the safety rules, but what about you, Mr. Producer? Don’t take chances. Read these safety reminders about silage safety.
Silo gases are created by the natural fermentation process shortly after chopped silage is placed in the silo. In sealed, oxygen-limiting silos both nitrogen and carbon dioxide gases form, but carbon dioxide is produced in significantly higher quantities, which helps maintain high-quality silage. However, the odorless and colorless carbon dioxide displaces the silo’s oxygen, giving producers little warning they are about to be asphyxiated. Because of this hazard, sealed silos are designed so that entering them is unnecessary, according to Penn State University Extension.
In conventional silos, nitrogen dioxide gas is frequently produced. This highly toxic gas smells like a strong bleach and can be visible as a yellow to brown fog. From a distance, it is sometimes mistaken for smoke. Nitrogen dioxide levels peak about three days after harvest and rapidly begin to decrease thereafter, particularly if the silo is ventilated. After two weeks it is unlikely more gas will be produced, although some hazard remains if the gas has not escaped the silo.
“If you must go up into the silo, measure for the gases to see if they're present and also run the blower to try to evacuate the gases from the silo before entering,” said Brian Holmes, Ph.D., emeritus professor at the University of Wisconsin. “However, there's no guarantee of safety because sometimes the blower doesn't reach down to where the gases are being generated. These gases can make you very sick … or kill you, and it doesn't take a lot of exposure. If you see brown gas or smell bleach, get out as quickly as possible.”
There’s always potential for dangerous gases; the biggest danger is during drought. Corn tends to accumulate nitrate in the stalk under drought conditions and is more likely to produce dangerous nitrogen dioxide gas.
The risk of falling down the chute as you're climbing up and down to access the silo is another safety hazard.
The silo unloader is easy to become entangled in, so be especially cautious near it.
Lock out and tag out the power supply to the silo unloader if you are entering the silo so somebody doesn't come along and accidentally turn it on when you're inside.
Chain conveyors, augers and PTO shafts are a significant risk. During the filling process, a tractor will be running a blower, so avoid being near the PTO shaft.
“Have proper shields in place and don’t get too close to the intake of the blower for fear of being dragged in, as this can be deadly. Self-unloading wagons have augers, so you want to avoid being in contact with them as well,” said Holmes.
Have a buddy system: never enter a silo unless another person is present and could go for help should you need assistance. Your buddy should maintain visual contact with you at all times. If gases are present you may lose consciousness before being able to call out for help, or other sources of noise may drown out your attempts to gain their attention.
Watch for our next article about silage safety for bunkers and piles.