Adair, whose Red Adair Co helped extinguish about 2000 oil well fires on land and at sea, died in a Houston, Texas, hospital on Saturday, his daughter, Robyn, said.
A pioneer in the dangerous field of capping oil well blowouts and fires, Adair's exploits were the stuff of legend and took him from the Middle East to Australia to Mexico and the North Sea.
John Wayne even made a movie about his life called Hellfighters. Adair served as a technical adviser to the 1968 film.
Born Paul Adair in Houston on 18 June 1915, one of eight children, Adair quit high school and went to work for the Southern Pacific Railroad in 1936, according to his official biography.
Red Adair Co developed new techniques and equipment for fighting oil well fires and blowouts on land and at sea, where submersible fire-fighting vessels were used.
Among Adair's most notable feats was the capping in April 1962 of an oil well fire in the Sahara Desert known as the Devil's Cigarette Lighter which had burned for 167 days and was so massive it could be seen by orbiting astronaut John Glenn in his space capsule.
Adair described extinguishing that fire as one of his toughest jobs.
His team also battled the June 1979 IXTOC 1 blowout in the Gulf of Mexico and the Piper Alpha disaster in the North Sea in July 1988 which left 167 people dead.
After the 1991 Gulf war, Adair, then 75, was called in to help extinguish fires at Kuwaiti oil wells set by retreating Iraqi troops.
His company managed to put out 117 oil-well fires in just nine months - a job that had been expected to take three to five years.
Adair, whose nickname came from a fondness for the colour red and who would sport red overalls on the job, sold Red Adair Co in 1993, but continued to serve in the industry as a consultant.