BTW, read this report ~ this sounds more like what happened in the garage than anything else I’ve seen: http://www.koverholt.com/wp-content/uploads/2010/02/California-explosion-report.pdf
" Interesting report. Both explosions described were from large amounts of antifreeze and water being sprayed from above by an automatic sprinkler system onto an open flame. The mist ignites instantly causing a massive explosion. In the first example it said the system contained 262 gallons of glycerine, and in the second, a large amount of p-glycol.
Trukee, in the winter had about 0% humidity. Interesting.
Thanks for your post. It looks like the physics of your antifreeze explosion is probably more similar to that of of a grain dust explosion than that of gasoline which exists as a vapor. The small particles from the mist have lots of surface area and can become quickly oxidized. I am not convinced that such a scenario existed in the garage. The vapor pressure of antifreeze at 20 degrees is likely quite low and not sufficient to cause an explosion. The pressure in a cold radiator would likely not be sufficient to make a mist of leaking fluid.
I guess I’m not convinced that the car lights and cooling fluid started the fire. However, once the fire got going enough and burned through the hoses it may have added to the flames.