04-06-2009, 02:18 PM #1
- Join Date
- Dec 2002
Here is the science behind wet hay heating up then spontaneously combustion!
Fire destroys greenhouse
By Vanessa Overholser - Staff Writer
A local greenhouse caught fire after a pile of hay and straw spontaneously burst into flames Monday afternoon, officials said.
The fire broke out in one of the greenhouses located at the More Than Mulch farm owned by Keith Kappes and his sons. Fire departments from Route 377 and Morehead rushed to 250 Gordon Lane near Weaver Hole Estates at 3:30 p.m. to put out the blaze.
“Two of our part-time employees were watering plants when one employee said he thought he smelled something burning,” Kappes said. “By the time they got there, the flames were shooting through the roof.”
The greenhouse contained a large pile of bales of hay and straw and some plants. Kappes said the hay and straw were the cause of the fire.
“It appears that it (fire) was caused by spontaneous combustion with the combination of hay and straw stored in a small space,” Kappes said. “Plus moisture was present from where it had rained.”
Jason Peace was one of the employees who discovered the fire. He recounted his events at the onset of the fire and what went through his mind as he reacted to the incident.
“We were in the second building when we smelled the smoke and we got out,” Peace said. “The first thing I thought of was to get out of the building and call 9-1-1. We started moving equipment.”
Tyler Fryman described the moments before witnessing the fire.
“I turned around and looked outside at the greenhouse next to us,” Fryman said. “It didn’t register at first when I saw it. I turned around and he (Jason) said ‘man that thing is on fire.’ We ran out and started moving equipment.
“The straw and hay pretty much exploded,” Fryman said. “I tried to put it out with a water hose but Jason said that won’t work. He was right. It didn’t work.”
Nobody was harmed during the fire, Kappes said.
“We are thankful nobody got hurt and for the quick response of the fire departments,” he said.
Ironically, Kappes and his staff had talked about moving the straw and hay to another location before the fire. The Kappeses had one problem. Their equipment was taken out-of-town to clean up areas in western Kentucky that were devastated by the recent winter storm. Then the straw caught fire on Monday.
Kappes was not worried about the extent of the loss caused by the fire.
“We are fully insured,” Kappes said. “The fire destroyed the greenhouse the hay and straw were in and it melted 40 percent of the plastic (exterior of building) on the greenhouse next to it. We had some plants lost. Most of the plants we have left can be salvaged.”
Director of the Morehead-Rowan County EMS and member of the Route 377 Fire Department Danny Blevins said it took a lot of water to put out the flames.
“It took four tankers (two from Morehead and two from Route 377) and 9,000 gallons of water to suppress the fire,” Blevins said. “Fire officials called for a backhoe to be brought on the scene to spread out the hay and straw so they could extinguish the fire.”
It took more than three hours for firefighters to battle the blaze and clear the scene. The fire remains under investigation by the Route 377 Fire Department
Beware of hay fires...
Wet hay favors the growth of organisms which generate heat and can increase hay temperatures up to 150 degrees F. Once hay heats beyond this point, chemical reactions take over and can increase temperatures to the point of spontaneous combustion. With "wet" hay packed tightly in bales and stacked together in large quantities, fires are very possible. Whether hay which is in this situation actually starts to burn or not depends mostly on the size of the stack and the material surrounding it.
If hay is stacked loose and sufficient cooling occurs at the same rate as the heat is generated, the hay may simply caramelize and turn brown or simply mold. However, if there is enough hay on the outside part of the hot spots to prevent the escape of heat, and the carbon, nitrogen, oxygen and moisture levels are right, a fire will eventually occur due to spontaneous combustion.
If you suspect that your hay may be heating up, the temperature can be measured and monitored by using the following process:
Drive a pointed 2" pipe into a hay bale and lower a thermometer on a string down into the pipe. Wait 10-15 minutes for the temperature to stabilize, then pull it out and read the temperature. Repeat this in several bales. If a thermometer is not readily available, drive a solid metal rod or pipe into the center of the bale and after 15-20 minutes withdraw the rod. If it is too hot to hold in your hand, the situation is critical. The temperature should be determined and appropriate action taken.
Actions to take...
If temperatures are below 140 degrees F there is not any danger, unless it is early in the process.
When the temperature is between 140-160 degrees F, check bales daily
If temperatures rise above 160 degrees F, check every 2-3 hours and prepare to move the hay from the building and spread out so that air can get around the bales.
If the temperature reaches 180 degrees F, notify the fire department, insurance company (if the building is insured) and remove all equipment and/on animals from the area. With fire equipment on hand (not just an extinguisher), remove bales to the outside and do not stack. Place in rows for easy access. During removal, be alert for burned out cavities. Also, hay under these conditions may flame up as fresh air strikes it or smolder in a pile for weeks.
If bales ignite, soak with water and force some water in the center of the bales.
If the bales do not ignite, try to save the hay by allowing the bales to simply cool down.
Continue to monitor the internal temperature of the bales. The hay may be put back in the building after the temperatures drop below 100 degrees F.
Last edited by coldfront; 04-06-2009 at 02:48 PM.Always a day late and a dollar short!
04-06-2009, 02:36 PM #2
Did you have a question about this or was this mearly a post letting everyone know that this happens??
Bottom line when you cut hay it should lay in the fields and dry before bailing and taken to the barn. You never bail wet or damp hay.
The same goes for tobacco; you never put wet or damp tobacco in a hogs head. I have fought more fires in them where the tobacco had been pack wet or damp.
Last edited by CaptOldTimer; 04-06-2009 at 02:38 PM.Stay Safe and Well Out There....
Always remembering 9-11-2001 and 343+ Brothers
04-06-2009, 05:00 PM #3
This has destroyed many a barn in my area.
barn fires suck.
Lots of work.
you get dirty and smelly.
Takes forever.Jason Knecht
Altoona Fire Dept.
IACOJ - Director of Cheese and Whine
EAT CHEESE OR DIE!!
04-06-2009, 08:55 PM #4
Whats the science behind wet hay heating up then spontaneously combustion?Logic and proportion have fallen sloppy dead.
04-06-2009, 08:59 PM #5
- Join Date
- Dec 2002
- Central NJ
04-06-2009, 09:05 PM #6
- Join Date
- Jan 2003
- Canuck Expat May be anywhere
This happens fairly often up here. On my old vol dept, we would get several a year. The absolute worst were the stacks of large square bales. Impossible to get a stream into the heart of the heat, some farmers always wanted to try and use their tractor and lift to move bales, but we would always stop them, based on the theory that the Good Lord would grow more grass, but he wouldn't probably look after damn fools. Most times the stack would be lost and we would only be able to stop it spreading.
04-06-2009, 10:09 PM #7
A couple of years ago, I had gone on to become an acting officer at my current suburban combination department when we responded to several large round bales burning on a construction site. With my previous experience, I knew our best bet was to break up the bales. This time, we used the smooth bore tip on the ladder pipe... We made a muddy mess, but the fire went out.
04-07-2009, 12:57 AM #8
04-07-2009, 01:32 AM #9
04-07-2009, 01:51 AM #10
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- Jan 2007
- St. Louis City Mo
I think it is mice with matches. But then again I am not a scientist.
04-07-2009, 07:24 AM #11
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- Feb 2006
04-07-2009, 10:12 AM #12
- Join Date
- Jan 2008
Hay that was too wet from rain or dew or that was not allowed to dry sufficiently in the field will
go through a curing process (sometimes referred to as a sweat) in storage. During the curing process,
heat is produced. This heat buildup is caused from live plant tissue respiration coupled with bacteria and
mold activity. Plant respiration converts plant sugars to water and carbon dioxide, increases neutral
detergent fiber (NDF) and acid detergent fiber (ADF) and decreases the net energy content of the hay.
Plant respiration slows as moisture content decreases but does not stop until plant moisture is 20% or
less. Mold organisms grow in hay having 20 to 35% moisture content. As with plant respiration, molds
likewise consume plant sugars, producing water and carbon dioxide, causing loss of dry matter,
digestible nutrients and net energy. The production of water through plant and mold organism
respiration can actually increase the moisture content of hay in storage (sweating) if the moisture is not
able to escape from the bale, mow (the pile of hay in the part of a barn where hay is stored), or stack.
Plant and mold respiration also generate heat. If the hay heats to 100°F or higher, browning
reactions begin (also called carmelization). In these reactions, proteins and amino acids combine with
plant sugars to form a brown polymer resembling lignin. This results in increased levels of ADF and of
acid detergent insoluble protein (bound protein) and reduced digestibility and net energy (Table 1).
Browning reactions release heat, and when coupled with heating from mold growth, result in an upward
spiral in temperatures of the hay mass. If the water generated by plant and mold organism respiration is
not able to escape from the bale, mow or stack, then what initially may have been a relatively small wet
spot becomes bigger and bigger as the heating drives moisture into hay surrounding the spot.
This will also occur with unsaturated fats.
Fire & Explosion Investigation
Spontaneous Combustion of Drying Oils as a Fire Cause
04-07-2009, 10:39 AM #13
- Join Date
- Jul 1999
- Flanders, NJ
Without a doubt, the science of spontaneous heating and ignition is easily the most misunderstood ignition scenario facing fire investigators today. In my experience, spontaneous ignition fires in hay barns are the same as electrical fires to many investigators. "There's hay there so it must be spontaneous ignition".
Spontaneous heating occurs when there is a chemical reaction and increases in temperature solely due to a exothermic reaction between the material and the surrounding atmosphere (NFPA 921 188.8.131.52.2.1)
There must be certain conditions present to allow self-heating to occur. First, the material must be capable of self-heating. Normally, these materials are organic and capable of reacting with oxygen. This material must be p orous, permeable and oxidizable. Secondly, the material must be subjected to conditions where self-heating is promoted. Thirdly, the self heating must exceed the rate that the heat can be dissipated. This phase is called "thermal runaway" (NFPA 921 184.108.40.206.3). This will cause a temperature where stable conditions no longer exist. Most materials will need an internal temp of a couple of hundred degrees C to promote self-sustained smoldering.
The process requires a delicate balance between insulating properties of the fuel package, and the available oxygen. Too much insulation and the fire will burn out. Too much oxygen and the heat will be dissipated and thermal runaway will not occur. This is entirely dependent on the shape and size of the fuel package and the environmental conditions.
DeHaan talks about this phenomenon in Kirk's 6th ed. on page 183. He addresses, in great scientific depth, the conditions that must be present. In essence, there must be a fermentation reaction caused by the death and decompostion of the present microorganisms. Again, this chemical reaciton will only cause smoldering ignition, which will then take over if the fuel package will reach thermal runaway.
He makes an important note that there must be a moisture factor in the reaction. He notes that partially cured (dried) hay will be most susceptible to self-heating. Well-cured (dried) hay will not self-heat. There is a difference between non-cured hay (internal moisture) and wet (from rain) hay. Cured hay that gets wet in the rain will not self-heat due to a lack of living microorganisms present.
In short, ideal conditions must be present for self heating and ignition to occur.
From the above description, you can see why it is utter nonsense to suggest that a 1' thick layer of mulch in the flower bed outside the house could self-heat. It can't. It is impossible. There must have been an outside heat source.
It is equally unlikely that you are experiencing "many" barn fires due to spontaneous ignition of hay. It is statistically impossible that these ideal conditions have widespread existence. It is more likely that those "many" barn fires are the subject of inadequate fire investigations.
This is not a shot at those fire investigators. The fire investigation community does a horrible job at teaching this subject.
Let me know if you need any other info.PROUD, HONORED AND HUMBLED RECIPIENT OF THE PURPLE HYDRANT AWARD - 10/2007.
04-07-2009, 10:54 AM #14
- Join Date
- Jan 2008
I also recall that there was an article on firehouse.com sometime ago that discussed this. It spoke to a fire in NYC where the workers had left linseed oil soaked rags in the stairwell. With te unsaturated oils it has something to do with breaking the carbon bond, thus creating heat.
We had a large wood chip pile a few years back catch on fire, It was probably 30 feet deep. In this case the bacteria that cause the decomposition create the heat.
As an experiment, mow your grass and pick up the clippings immediately, placing them in a large metal garbage pail. If you use plastic DO NOT put it in your garage, shed, or house. Wait about a week or so and stick you hand down inside. If you can, put a temperature probe down inside. Make sure the thermometer goes to at least 200 degrees.
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