Fire and hazmat crews have donned protective suits to extinguish a rare and toxic sulphur fire in the western US state of Wyoming.
The blaze erupted when a sulphur mound caught fire at a recycling plant in the city of Worland on Friday.
Hypnotic video uploaded by Worland Volunteer Fire Department shows mini “firenadoes” swirling through the air as crews worked to safely stamp out the flames.
“This is a type of fire that is not common but needs to be addressed and dealt with safely and quickly,” Worland Volunteer Fire Department said.
Burning sulphur creates sulphur dioxide, a hazardous gas with a strong odour, which can turn into a sulphurous acid with the addition of water.
Local fire crews said the fire was burning in a “bowl shape”, allowing all runoff to be collected in the fire area.
A small amount of water was used to cool the surface of the sulphur and reduce the temperature below the molten stage.
The sulphur deposits in the rural Washakie County are left over from the Texas Gulf Sulphur Plant that operated north of Worland in the 1950s.
Much of the sulphur is mixed heavily with soil and is not 100 percent sulphur concentrate.
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