On July 7th, fire chief Chris Kocher at the Worland, Wyoming volunteer fire department received a phone call alerting him of a “blue glow” in a rural area off Highway 20 North. As soon as he arrived onsite and looked at the blazing area through binoculars, “I saw we had a sulfur fire,” Kocher tells The Verge.
The fire looked like a carpet of sparkling blue blaze. In a video posted by the fire department on Facebook — which has been viewed almost 2 million times — you can see flames moving quickly across the surface, sometimes raising up into the air. It’s mesmerizingly beautiful — and also really dangerous. If you breathe the smoke, it can harm your lungs and even kill you.
When sulfur burns, it produces sulfur dioxide, a harmful gas that forms sulfurous acid when it comes in contact with water, including the moisture in your lungs. Sulfurous acid is related to acid rain, which can kill trees and fish. To keep safe, the firefighters at the scene were wearing a self-contained breathing apparatus, which is why in the video you can hear a Darth Vader-ish breathing noise (as The Washington Post points out).
Putting down a sulfur fire isn’t the same as dealing with a regular fire: in fact, the crew used only a small amount of water from the fire truck plus firefighting foam. That way, the temperature of the sulfur could be cooled down below 309 degrees Fahrenheit — when it’s in a molten stage — so that a crust formed at the surface. “And then the fire’s out,” Kocher says. The whole thing took about 20 minutes.
The sulfur mound is leftover from the Texas Gulf Sulfur Plant, which operated north of Worland in the 1950s. The sulfur is mixed heavily with soil, the Facebook post says. It’s not 100 percent sulfur concentrate, but it’s still highly flammable. The 10,000-square-foot area that went ablaze Friday night was accidentally ignited by the exhaust of a motorcycle, Kocher says. The area hadn’t seen a sulfur fire in about 12 years, but the crew was prepared because there are a lot of oil fields around Worland, so the firefighters know how to deal with sulfur dioxide.
As for the viral video, Kocher says he was surprised to see all the media attention. You don’t see a bluish blazing field every day, and that’s probably what got people hooked. “It’s interesting to see how far the video has traveled,” he says.