It happened on the 19000 block of Stone Lake Drive in northwest Harris County, in the Tomball area.
"When I pulled up, an ambulance was here, Life Flight was here," said neighbor Larry Butterfras. "I came down to see what's going on and they said there was an explosion from the paint sprayer."
"It just sounded like a big bomb," said Linda Haidamous, who lives directly across the street from the house. "Very loud, (similar to) when a transformer blows."
The two men suffered burns and other injuries. One was transported by air ambulance, the other by ground ambulance.
According to the Harris County Fire Marshal Office, the explosion was caused by built up paint fumes.
"They were doing some painting and construction work," said Fire Marshal Office Deputy Chief Dean Hensley. "It appears we had a flash fire from vapors building up, the paint and fumes, and we had ignition source inside the house. We believe it to be the pump, but we're still investigating that right now."
Investigators say the men will survive their injuries. It's uncertain how long it will take to repair the home. Neighbors say they learned a lesson, that proper ventilation is key to avoiding flash fires and explosions.
"I've never heard of a paint sprayer blowing up, but obviously they can," said Butterfras.
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