The woman's 84-year-old sister doused the flames, which didn't extend to their home in Bogert's Trailer Ranch on Pulis Avenue, Lt. Jeff Dino said.
The victim was boiling a pot of water on the stove just before noon at Bogert's Trailer Ranch when it suddenly spilled, Dino said.
As she spun to get out of the way, her robe landed on the stove, where it caught fire, he said.
Flames were climbing her back as her sister came to her aid, the lieutenant said.
The victim was taken to St. Barnabas Medical Center in Livingston, they said.
Township firefighters and Mahwah EMS also responded.
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