I worked in the fertilizer business and my company sold ammonium nitrate to farmers, mostly for use on potatoes. You need to use extreme care with this fertili

I worked in the fertilizer business and my company sold ammonium nitrate to farmers, mostly for use on potatoes. You need to use extreme care with this fertilizer. No one could purchase it (even before Oklahoma City) without us knowing them. After Oklahoma City some TV stations in Grand Rapids sent reporters undercover trying to make purchases and they failed. You need either dynamite or a substantial amount of heat to cause ammonium nitrate to explode. My boss tried to create a farm pond with it and his initial attempt failed. He failed to use enough dynamite ;<). Personally I'd nominate the Beirut Port Authority for a Darwin award. Without the fireworks being stored in the building the welders sparks wouldn't have caused the explosion.