High-moisture haystacks and bales can catch on fire because they have chemical reactions that build heat. ... When hay's internal temperature rises above 130 degrees Fahrenheit (55 degrees Celsius), a chemical reaction begins to produce flammable gas that can ignite if the temperature goes high enough.
How does hay self combust?
What is spontaneous combustion? Spontaneous combustion occurs when moist hay heats up due to a combination of natural microbial and chemical reactions. If enough air (oxygen) is present the moist hay may get hot enough to ignite, with fire then spreading through the stack or shed.
How do you keep hay from catching fire?
Another way to reduce the risk of a hay fire is to ensure that stored hay remains dry.
- When storing hay inside, make sure the barn or storage area is weathertight and has proper drainage to prevent water from entering the barn.
- When storing hay outside, cover the hay with plastic or another type of waterproof material.
