Farmers warned of danger of 'spontaneous combustion of wet haystacks' as barn fires increase
Farmers in Shropshire have been warned of the dangers posted by the spontaneous combustion of wet haystacks.
Shropshire Fire and Rescue Service says it is seeing an increase in barn fires containing stacked hay and say that "wet hay is more likely to lead to spontaneous combustion than dry".
Firefighters say that hay fires generally occur within six weeks of baling and heating of the wet hay usually peaks within three to seven days.
Fire crews across the county have responded to barn fires in recent weeks.
Shropshire Fire & Rescue Service advises farmers to check regularly and has more farm safety advice online at ow.ly/nill50PbCAC
Scientists at North Dakota State University in the USA say high-moisture haystacks and bales can catch on fire because they have chemical reactions that build heat. The larger the haystack, the less cooling that occurs to offset the heat.
When hay’s internal temperature rises above 55 degrees Celsius a chemical reaction begins to produce flammable gas that can ignite if the temperature gets high enough, they say.
