"Horvath" wrote
Flash Point
The flash point temperature of diesel fuel is the minimum temperature
at which the fuel will ignite (flash) on application of an ignition
source under specified conditions. Flash point varies inversely with
the fuel's volatility. Flash point minimum temperatures are required
for proper safety and handling of diesel fuel. Due to its higher flash
point temperature, diesel fuel is inherently safer than many other
fuels such as gasoline.

Diesel is an inherently safer fuel only because its flash point in
significantly lower than that of gasoline. I've watch a (idiot!) diesel tank
driver throw a lighted match into a 7000 gallon tank of #2 fuel to prove
that in a discussion. I don't recommend that, however.
The flash point of #2 fuel (diesel) is 110 deg Fahr, significantly higher
than that of gasoline (- 45 deg Fahr), which is right around the boiling
points of R-22 and Propane! Gasoline is more volatile, but once past its
flash point, diesel packs more punch (more btu content).
I think part of the explanation for diesel fires is that people become
complacent due to diesel's initial forgiveness factor. Let's not forget that
it was a fuel characteristically close to diesel that took down the towers
on 911.
Scout