Conventional Silo Firefighting

• Historically no threat of explosion. However, prolong advanced burning and applying water can weaken concrete staves and cause them to crack and fall.
• Aggressive attack rarely needed.
• Confined-space issues must be addressed.

Upon arrival to a conventional silo fire:

• Establish incident command & an accountability system.
• Perform a 360-degree evaluation, checking for exposure problems.
• Confirm your pre-plan information on silo.
• Have the farmer respond, if not there already.
• Have the farmer move any livestock, machinery,etc., from the immediate area if it can be safely.
• If not already done, raise the silo unloader to minimize the damage to it by the fire.
• Disconnect and lock-out/tag-out electrical supply to silo and silo unloader.
• If it can be done safely, a FF climbs the silo exterior ladder or exterior chute and assesses fire from above. Thermal imagery may be useful. Utilizing a ladder truck , if available, can be valuable. Be sure of a solid base for the truck. Use extreme caution when climbing as ladders and steel rungs can be slippery and/or damaged.
• Once above the fire, FF's can direct water onto the hot spots. A fire in a conventional silo is typically located around the silo perimeter, the unloading doors, and the first few feet of silage. Fires burning for an extended time can create hollowed-out cavities.

• There is typically no value and high-risk to entering the silo.
• Adjustable length penetrating nozzles may be useful.
• No proof that foam or other additives helps extinguish deep-seated fire.
• It is usually impossible to completely extinguish fire. Cool it enough for the silo unloader to be brought back in service.
• Even when it appears extinguished, it often re-ignites.
• The farmer must partially or totally empty the silo.
• Silage may flare up during unloading.
• This is an extended operation. Rotate personnel and/or lend the farmer a portable pump and hose if safe to do so.
• Value of using carbon dioxide is questionable. Some departments have had success.

Oxygen-Limiting Silo Firefighting

• It is imperative that firefighters be able to identify these silos.
• Firefighters are killed when they inject water or foam into the burning silo.
• Since these structures are designed to limit the air that enters — smoldering fires
• result.
• Combustible carbon monoxide is produced and contained by the silo.
• Allowing air into a carbon monoxide-rich atmosphere is dangerous.
• THEREFORE, DO NOTHING THAT WILL CAUSE MORE AIR TO BE DRAWN INTO THE SILO. Do not open hatches or spray water inside.
• Remember there are many different brands of oxygen-limiting silos.
• Some are metal, some poured concrete.
• Many firefighters have been injured and killed employing incorrect tactics.

Upon arrival to an Oxygen-limiting silo fire:

• Establish incident command & accountability system.
• Perform 360-degree view, checking for and handling exposure problems.
• Confirm Pre-Plan information on the silo involved.
• Have the farmer respond, if not there already.
• Have the farmer move any livestock, machinery, etc. from the immediate area if it can be done safely.
• Do nothing that will increase the amount of air inside the silo. Do not open any hatches or unloader doors and do not inject any water or foam.
• If the silo is shaking, hot, noisy, smoking heavily, or has been opened up in the past few days, stay off it. Create a 50 yard hazard area around the silo.
• If the silo is quiet, motionless, and cool and smoking minimally, and has not been opened in the past few days, close any open hatches and doors. Do not re-open these once closed. If in doubt, do not climb the silo !
• If the silo is well-sealed, the fire may self-extinguish. If the fire continues to burn after two weeks, carbon dioxide or nitrogen gas may be injected to extinguish the fire. Harvestore repair people are able to assist with this operation. The farmer will need to empty the silo. Hot silage leaving the silo will need to be dealt with.

Modified Silo Firefighting

• Less is known about firefighting in Modified Silos.
• One case in New York, a Harvestore that was modified into a "conventional" silo, with doors cut into the side of the silo, exploded once water was injected from above.
• Rescuers must be able to distinguish between silos in order to safely fight fire in them.
• Treat these silos like Oxygen-Limiting in fire conditions.
• Request expert advice.

Summary

• Firefighters need to preplan farms.
• Distinguishing between silos is critical.
• Firefighters need to train in this area.
• The possibility of firefighters causing an explosion is there.
• Securing qualified technical assistance critical as there is rarely a need to act hastily.