Grain Storage and Handling

Contents:

Auger Safety Human Health Concerns from Grain Dusts and Molds During Harvest Grain Dust Respiratory Hazards

Keeping grain in proper condition is the first step in preventing entrapment in flowing grain. Many grain entrapments have occurred when a person went into a bin to break apart moldy or crusted grains. Good bin management will help prevent moldy grains and spoilage.

Enter a bin only if absolutely necessary.  Instruct family members, especially children, and employees on the hazards of entering grain bins and dangers in flowing grain. Flowing grain is also a hazard with gravity wagons.

Use a pole to break up grain bridges from outside the bin.  If you have hauled out grain and the grain surface is at the same level, this is an indicator that there’s a grain bridge. You should see a funnel shape on the grain surface after grain has been removed. The hollow cavity under a grain bridge will be equal to the volume of grain that has been removed. A grain bridge will not support a person’s weight.  The pole should be attached to a rope tied to the outside of the bin. If you drop the pole, it can be retrieved using the rope and save you from entering the bin.

If you need to enter a bin:

• Lockout/tag-out power to augers or other powered equipment before entering bin.  If augers are operating, the flowing grain will pull you down in a matter of seconds.
• Use proper PPE as air quality may be reduced by mold and dust. Use a NIOSH approved dust respirator to prevent exposure to high levels of dusts or molds.  If the grain has become moldy, the molds will produce carbon dioxide. The carbon dioxide can displace the oxygen in the air causing an oxygen deficient atmosphere. Use a gas monitor to test oxygen levels before entering bin.

• Use a body harness and safety line secured to the outside of the bin when entering. An anchor point and safety line should be able to hold 5,000 pounds of force. The body harness and safety line may not prevent you from being caught in flowing grain. It will help rescuers locate you and the body harness gives rescuers some place to attach retrieval systems.

• Have at least two trained observers during grain bin entry. Discuss communication plans and actions to take in case you become entrapped in flowing grain. Instruct them to not enter to rescue but to call for rescue assistance.

• Use hand signals to communicate. Other communication devices may not work inside a bin.

• Work from top to bottom when cleaning grain bin walls. Any grain piled higher than your head has the potential to collapse and avalanche down on top of you.
• Check that an entry permit has been issued and safety precautions have been taken to make a safe entry.

If rescue is required:

• Shut off all grain-moving machinery. It is important to stop the flow of grain.
• Contact the emergency rescue service or local fire department.
• If possible, ventilate the bin using the drying fan without activating the heat source.

It’s time to move the auger to a new grain bin or a different facility. Here are a few safety reminders when transporting and placing an auger.

Transporting

• Transport your auger empty and in the lowered or “full down” position. The lift arm of the undercarriage should be seated against the down position stop with slight tension on the winch cable and at least three complete wraps of cable around the winch drum.
• The hitch pin should be securely attached and a safety chain secured between the auger and towing vehicle.
• Do not transport the auger at speeds in excess of 20 MPH. When traveling on the highway be sure to have the auger properly marked with a Slow Moving Vehicle (SMV) emblem.
• Be alert to overhead obstructions and electrical wires. Remember, electrocution can occur without direct contact, due to arcing. Failure to stay clear of electrical wires will result in electrocution.
• Never allow persons to stand underneath or ride on the auger when it is being transported.
• Never move the auger manually. Use a vehicle. When releasing from or attaching to the vehicle, test the intake end for downward weight. Lift it slowly and keep the intake end no higher than the vehicle tow bar. Don’t push the undercarriage.

Placement

• The auger must be on a level surface, attached to a vehicle, and wheels must be free to move when raising or lowering. Keep the travel distance to a minimum when placing a raised auger.
• During placement, make sure the entire area above the auger and in the line of travel is clear of obstructions and electrical wires. Failure to stay clear of electrical wires will result in electrocution.
• Move the auger slowly into the working position with the towing vehicle, not by hand. Make certain everyone is clear of the work area.
• Once in the place, the auger should be anchored at the intake end and/or supported at the discharge end. The wheels on the auger and the power source should be chocked on both sides.
• Do not attempt to increase auger height by positioning wheels on lumber, blocks or by other means.

Additional Safety Items

Common injuries with augers include amputations, lacerations, broken bones and electrocutions. Taking a few precautions can help prevent these injuries.

Keep shields and guards on augers and PTOs. The intake screen is an important safety feature that allow grain to flow through but keep hands and feet out. Replace any damaged intake shields or install on older augers that might have been purchased without an intake screen. If you are using a PTO driven auger, follow all precautions for operating a PTO including having the proper shielding in place.

Establish a work zone. When operating an auger, having a work zone helps to keep children or visitors out of a very dangerous area.    Numerous injuries with augers have involved children who fell into augers or unknowingly placed their hands into a running auger. Post a few signs or use temporary markers to help instruct family members or visitors to stay out of the active work zone.

When kept in good maintenance with shields and guards in place and following safety procedures, augers are valuable pieces of equipment for moving grains and feeds.

Exposure to Grain Dusts and Molds

If you produce corn, soybeans, or other crops in Wisconsin or elsewhere in the Midwest, dust exposure while working is inevitable. Breathing in grain dust can affect the health and overall comfort for grain producers and others who work in the grain industry. Exposures can occur:

• In the combine
• While unloading
• During drying and processing
• In bins
• In an area near any of the above situations
• While grinding/mixing grain and other feed products

Grain dust is a complex soup that is made up of both organic and inorganic particles. Some of these can be inhaled easily, and depending on their size, can find their way deep into various parts of the respiratory system causing a range of adverse health effects. Grain dust is biologically active and is made up of a combination of:

• Plant material
• Mold and mold spores
• Insect parts and excerta
• Bacteria
• Endotoxins (toxins contained in the cell walls of some bacteria)
• Soil

Exposure to Small Concentrations During Normal Work

Most people will have some reaction to dusty conditions during grain harvest. Often, this will be a nuisance reaction or irritation, but in some cases, more problematic health problems are possible. Even in the cab of a combine, there is some level of dust (1 to 15 mg per cubic meter), and endotoxins (even with a sealed cab and proper air filtration) can reach limits that cause health issues and symptoms for some. At low levels that a healthy person might encounter during the harvest season, developing a cough might be common (intermittent with more phlegm when actual work exposure is happening). Other symptoms can include:

• Chest tightness and/or wheezing
• Slightly sore/irritated throat
• Nasal and eye irritation
• A feeling of being stuffed up and congested all the time

Both chronic and acute bronchitis can also be common among those who handle lots of grain throughout the day as the main passages in the lungs get inflamed. Grain dust can also be a significant problem for those with asthma.

Exposure to Higher Concentrations of Grain Dust

Higher concentrations of dust exposure like you might encounter behind a combine, in a bin, or while unloading or processing grain are a concern especially this year with moldy and low test weight grain that might be more dusty and prone to damage. Moldy, damaged, dusty grain can cause significant issues for people. For many individuals, a heavy dose of dust even for a short time period can result in symptoms that occur a few (2 to 6) hours after exposure and may particularly noticeable after they’ve gone home at night. These symptoms can include:

• Cough
• Chest tightness
• Malaise-general feeling of discomfort, illness or feeling “ill-at-ease”
• Headache
• Muscle Aches
• Fever

Specific Reactions Caused by a “Massive” Exposure to Moldy Grain

Most people who have worked around grain will occasionally find themselves in a situation that is obviously very dusty. This “massive” exposure to a cloud of dust is something that should be avoided, though that is not always possible or practical. A massive exposure to moldy, dusty grain as well as other agricultural products (hay and silage in particular), even for a short period of time can result in two distinct medical conditions that look VERY similar and have the same cluster of symptoms outlined above (cough, chest tightness, etc.). These two conditions are “Farmer’s Lung” or Hypersensitivity Pneumonitis (FHP) and “Organic Dust Toxic Syndrome” (ODTS).

“Farmer’s Lung” or Hypersensitivity Pneumonitis (FHP) is fairly uncommon and generally affects about 1 in 20 farmers. Many complaints by farmers to their health provider get mislabeled as FHP. FHP is a delayed allergic reaction that is caused when highly sensitive people breathe in grain dusts and their bodies produce “antibodies” as a reaction to the dust. Since FHP is an allergic reaction and involves the body’s immune system, repeated exposures and bouts with FHP can get worse with each exposure. Some individuals may become physically unable to work in dusty areas and can develop permanent lung damage. FHP is most often brought on or made worse by molds and bacteria that grew under warm/high heat conditions. These heat-loving organisms are more likely to grow in stored hay or sometimes in the top layers of stored silage as compared to grain that has been standing out in the field, though exposures that lead to FHP can occur from grain. If you’ve been diagnosed with FHP before, and get sick this year while working around grain, it is a good idea to see your family doctor.

“Organic Dust Toxic Syndrome” or ODTS, as the name suggests, is a toxic reaction as compared to the allergic reaction that causes FHP. The respiratory system can get inflamed from the dust, molds, bacteria, and endotoxins in grain dust. With ODTS, people develop a general reaction that looks very similar to FHP even though the actual reaction by the body that causes the symptoms is quite different. People who develop ODTS will usually recover in a few days and permanent lung damage is not likely to occur with a single exposure, but they may feel fairly sick (fever, fatigue, cough, chest tightness, etc.) for a few days after exposure. Again, your family doctor should be consulted if you develop this type of reaction. It is possible that repeated occurrences of ODTS can lead to FHP in some people, so prevention is important.

A difficult problem is that since Farmer’s Lung (FHP) and Organic Dust Toxic Syndrome (ODTS) have such similar symptoms, it is hard for health professionals to always recognize and know the difference. Additional medical testing will be needed to tell the two apart. Medical treatment is also different. References cited at the end of this article might be helpful for your physician if you visit your doctor’s office with serious problems that you think might be connected to harvesting or handling dusty and moldy grain. Another concern in late 2009 is that the respiratory symptoms that result from heavy grain dust exposure can look much like influenza (seasonal flu or H1N1). If you’ve been working in dusty conditions and end up with a “flu-like illness,” make sure you let your healthcare provider know you’ve had significant dust exposures.

Controlling Exposure Risks

Grain dust exposure and the associated problems and health symptoms are complex. Here are some specific things you can do to control your risk:

• Have the correct and clean air filter in place when operating the combine. Use the appropriate setting on the blower in the cab whether you are using the heater or A/C. This will minimize dust concentrations in the cab. When replacing filters, make sure all gaskets are intact and that the air is being well-filtered.
• Avoid direct exposures to dust whenever possible,regardless of your sensitivity. Stay in the cab when unloading. Use the wind to your advantage rather that standing directly in a cloud of dust any time grain is being moved.
• Properly adjust your combine to minimize grain damage. This will help to also minimize the amount of dust being generated.
• Wear a NIOSH-approved and certified “N-95” dust mask (respirator) that fits you properly. Especially, if you find yourself working in a very dusty situation that cannot be avoided. Caution: Wear a respirator only if you are free of health problems, particularly with your heart and lungs. Respirators are only effective if you are cleanly shaven. Local health professionals can be a great source of information and can recommend the type of respirator that can be safely worn. If you work in a facility where worker safety regulations for respiratory protection apply (such as a grain elevator or feed mill), there are other regulatory requirements before a dust mask can be worn by workers.
• Avoid dust exposure if you have any chronic respiratory health issues, including asthma, previous experience with FHP, or existing respiratory infections or conditions. Individuals who have these conditions should be alert for symptoms, even when working in a relatively clean environment like the cab of a combine, and should minimize their exposure to dust.
• If feeling sick, call your health care provider. If you find yourself working in a very dusty situation (like loading or cleaning out a bin or getting a heavy, prolonged exposure near a combine in the field) and end up feeling sick a few hours later, call for medical advice. Again, your problem may be a condition like ODTS or FHP, but you may also have influenza or another illness.
• Smoking tends to make any type of symptoms or reaction caused by dust exposure much worse. Realize that smoking increases the risk of developing respiratory diseases such as emphysema and chronic bronchitis.

Authors:

John Shutske, Paul Esker, UW-Extension, Cooperative Extension and UW-Madison, College of Agricultural and Life Sciences

Steve Kirkhorn, MD, Medical Director, National Farm Medicine Center – Marshfield Clinic

References:

Kirkhorn SR. Agricultural Respiratory Health in Critical Need. Partners in Agricultural Health. Wisconsin Office of Rural Health. Available at: http://www.worh.org/AgHealth

Donham, K. J. and A. Thelin. 2006. Agricultural Medicine: Occupational and Environmental Health for the Health Professions. Ames, Iowa: Blackwell Publishing. (Chapter 3 contains information that can help a doctor in the process of differentiating between Farmer’s Lung and ODTS).

Girard M, Lacasse Y, Cormier Y. Hypersensitivity pneumonitis. Allergy. 2009 Mar;64(3):322-34. Epub 2009 Feb 6. Review.

Kirkhorn SR, Garry VF. Agricultural lung diseases. Environ Health Perspect. 2000 Aug;108 Suppl 4:705-12. Review.

Seifert SA, Von Essen S, Jacobitz K, Crouch R, Lintner CP. Organic dust toxic syndrome: a review. J Toxicol Clin Toxicol. 2003;41(2):185-93. Review

Grain dust can be a mixture of particles of grain, soil, plant material, fungi, bacteria, residues of agricultural chemicals and the excreta of insects, rodents and birds. The mixture varies with the type of grain, growing conditions and how it was harvested, stored and processed. Spoiled grain is especially contaminated with dust and bacteria.

These dusts can affect the respiratory tract in a variety of ways (see table below) and can cause gastrointestinal problems, skin rashes and eye irritations. Individuals may react quite differently to the same dust. Each person’s work history, health status and smoking history is unique. Thus, some people may be quite sensitive to the dust while others may be able to withstand several exposures prior to becoming sensitized.

Respiratory Problems Caused by Grain Dusts

Personal Protective Equipment (PPE)

To help reduce and prevent allergic reactions, a person should wear adequate protective devices or PPE, such as dust masks or helmets, and provide ventilation to remove the dusts. Those sensitive to the dusts should not enter areas where the dusts exist. “One-strap” disposable dust masks are not nearly as effective as “two-strap” models. Two-strap models fit better and allow less air leakage. Use NIOSH approved respirators or N95.

Warning! The simple dust mask will not protect a person against fumigants or areas where there is an inadequate supply of oxygen. These masks will not filter out harmful poisons nor will they add oxygen when there is an area with high concentrations of carbon dioxide resulting from the deterioration of wet grain.

Carbon Dioxide. If the presence of CO2 is suspected, do not enter the area. Opening manholes and all side door openings, supplemented by forced ventilation through the area, will help reduce the hazard. If ventilation is not possible, measure the oxygen concentration before entering. Do not enter if oxygen concentration in the area is less than 19.5%. A gas monitor will be needed to accurately measure oxygen concentration. Check with confined space entry procedures before entering the bin.

Source:

This material was adapted from “Safe Measures in Storing and Handling Grain”. Kramer, John. Kansas State University Cooperative Extension Service. Available here. Accessed August 24, 2007.