Steven McCormack, 48, said he fell from the rigging between his truck and the trailer at Waiotahi Contractors in Whakatane and he landed on the hose connected to the vehicle's air brakes, the New York Daily News reported Wednesday.
McCormack said the nozzle pierced his left buttocks and began pumping air into his body at 100 pounds per square inch.
"I was blowing up like a football," he said. "I had no choice but just to lay there, blowing up like a balloon."
Doctors said the air separated fat from muscle, caused his lungs to fill with fluid and compressed his heart.
McCormack was rescued by coworkers and taken to an intensive care unit at a Whakatane hospital. He said it took nearly three days for his body to deflate to normal size.
"You just have to burp it out, or fart it out," he said.