The blast, which followed the January explosion of another Federal Emergency Management Agency trailer, appeared to have been sparked by a lit cigarette igniting propane gas that had seeped into the travel camper, fire officials said.
Linda Meyer said she and her husband escaped through a portion of the trailer that was blown off by the explosion Wednesday morning.
John Meyer, 49, was hospitalized with third-degree burns over 40 percent of his body. Linda Meyer, 54, was treated for second-degree burns on her hand, authorities said.
"I imagine he's going to take this real hard," said the husband's brother, Joseph Meyer. "At least after the storm he had his health."
FEMA spokeswoman Rachel Rodi told The Times-Picayune newspaper for its Thursday editions that the agency briefs all trailer residents on fire safety precautions before they move in. She stressed that residents should contact FEMA immediately if they smell anything suspicious or suspect a gas leak.
The Meyers had been in the trailer for about four months and had noticed an odor in recent days but didn't suspect a propane leak, Linda Meyer said. She said she didn't know where they would live now.
In January, another FEMA trailer exploded in Harvey from an apparent propane gas leak, inflicting second- and third-degree burns on two contract workers who were checking it before delivery, the newspaper reported.