Preventing and preparing for grain dryer fires
The devastating results of fire can include death, serious injury, financial loss, property damage, business interruption and production downtime.
Grain dryer fires are one of the most significant risks a grain handling operation can face. The devastating results of fire can include death, serious injury, financial loss, property damage, business interruption and production downtime.
Take a proactive approach to grain dryer fire management by developing a pre-incident fire plan. These plans can help decrease fire severity by addressing common causes, reduce damages with early fire detection, detail proper response techniques for extinguishing and explain how to continue operating with key assets impaired after a loss.
Our loss history indicates that grain dryer fires commonly occur in continuous-feed crossflow grain dryers and the information presented here has been tailored to address fires in this type of dryer. Additionally, our loss history has shown that soybeans and sorghum are more frequently involved in grain dryer fires than other types of grain commodities.
Pre-incident fire plans should be used to supplement your grain dryer manufacturer’s operating manual along with input from your local fire department. Invite the fire department to survey your facilities and incorporate their suggestions into your pre-incident fire plan.
While pre-incident fire plans are a good risk management practice, they should not be construed as a guarantee that catastrophic loss will not occur. There are no guarantees of the successful extinguishing of every type of grain dryer fire.
A fire watch is critical to an effective pre-incident fire plan. Continual observation is used to identify initial signs of fire or abnormal operation.
Since grain dryers are seldom outfitted with fire suppression systems, early fire detection can help decrease the severity of damage and increase the likelihood of successful extinguishing.
A continuous fire watch should occur whenever the grain dryer is in operation and at least 30 minutes after equipment shutdown as some fires start shortly after equipment is turned off.
The fire watchperson should be familiar with the grain dryer operation and be able to identify indications of smoke or fire by sight or scent alone. They should also be able to recognize abnormal operating conditions, such as excessive grain trash accumulation or a plugged grain column.
For example, the fire watchperson should be able to distinguish a smoky odor from normal operational odors and be able to discern a plume of smoke from steam at night when lighting is poor. Consider installing exterior flood lighting to illuminate the grain dryer and help improve the fire watchperson’s visibility during nighttime operations.
Additionally, the fire watchperson should know how to de-energize the grain dryer and shut off fuel supplies if a fire is suspected.
Fire department protocol
Your pre-incident fire plan should detail protocols for contacting the fire department – immediately upon suspicion of fire or after site personnel have investigated and confirmed the need for assistance. This decision is based on your organization’s unique risk tolerance.
Shutting down the grain dryer
If the fire watchperson suspects a fire, they should shut down the grain operation immediately by:
- Stopping grain flow in and out of the dryer
- Turning off all electricity serving the dryer
- Shutting off the dryer’s fuel supply
The grain dryer should have two fuel supply disconnects – One near the dryer or dryer controls and another disconnect some distance away. This helps enable site personnel to disconnect the fuel supply during a severe fire that prevents them from safely accessing the disconnects near the dryer.
Locating a fire
Upon suspicion of fire, the fire watchperson should retrieve a fire extinguisher and investigate whether the fire is in the plenum space, near the burner or within a grain column.
At least one pair of 10 lb. ABC fire extinguishers should be kept near the dryer or dryer controls, as well as a high-lumen flashlight to investigate nighttime fires or fires in the plenum space.
Common locations of grain dryer fires include the:
- Grain column turning mechanisms
- Transition between wet garner bin and vertical grain columns
- Horizontal surfaces at the transition from the burner section to the heating section
Your pre-incident fire plan should identify a responsible individual to evacuate customers and unnecessary personnel from the facility in the event of a grain dryer fire.
Extinguishing flames in the plenum space or burner area
Fires in the plenum space or near the burner can generally be extinguished with water. When the fire is located, assess whether site personnel can safely put out the fire with water or an extinguisher. If personnel cannot gain safe access or are unsuccessful in extinguishment, contact the fire department if they were not already summoned based on your organization’s protocol.
Personnel must be mindful that opening man doors to inspect or extinguish these types of fires may re-introduce oxygen into the plenum space and result in a flash fire. The risk of a flash fire increases as time passes, so early detection and identification is key.
Flushing grain columns for extinguishment
Grain column fires are typically extinguished by ‘flushing’ the column with wet grain. To do so, resume feeding the grain dryer with wet grain, but leave fans, reclaim conveyors and legs de-energized and the fuel supply shut off. Open the grain column dump gates at the base of the affected and adjacent columns and flush the columns with wet grain. Do not allow the grain columns to empty and add oxygen to the fire. Be prepared to apply water to grain on the ground after it exits the dryer or have the fire department available to do so.
Ensure the wet grain conveyor and wet grain leg serving the dryer are wired independently from other electrical circuits serving the grain drying operation. This allows the operator to flush the grain columns when the electricity is shut off to the rest of the operation.
When preparing your pre-incident fire plan, verify that your dryer installation allows for ease in dumping of the grain columns. If an obstruction, such as control panels or adjacent bin foundations, impedes the flow of grain from the column dump gates, your plan should recognize that suitable equipment, such as front end loaders or shovels, will be needed to move grain.
Business continuity after a fire
The aftermath of a fire can mean confronting various losses – death or serious injury, financial loss, property damage, business interruption and production downtime. Take time to develop a business continuity plan before an incident occurs to help you prepare for the impact of a grain dryer fire.
For instance, your organization will need to identify how to continue accepting and drying grain if a grain dryer is impaired for a significant amount of time. You should also prepare a statement for local and social media outlets as these events often make headline news in smaller communities.
A proactive approach to fire management, including a pre-incident fire plan, can help your organization prevent fires before they start, minimize damages with early detection and know the proper methods of extinguishing. Thorough preparation and planning can help your organization recover successfully.