How NIST justifies the discrepancy of
more than 450 degrees Celsius (or 842 degrees Fahrenheit):
A spray burner generating
1.9 MW or 3.4 MW of power was ignited in
a 23 ft by 11.8 ft by 12.5 ft high compartment.
The temperatures near the ceiling approached 900 ºC.
(p 123/173)
1.9 to 3.4 MW (megawatts) is the heat output of about 500 wood stoves --
in a living-room-sized space!