It’s hot outside, and you’ve got fireworks in the car. Is there any chance of a spontaneous explosion? No, but here’s what you need to know to be safe and smart while transporting fireworks.
Can You Keep Fireworks In A Hot Car?
Yes. Though it isn’t best practice, you can keep your fireworks in a hot car. They will not explode from sitting in a hot car or trunk. The explosive element in fireworks, black powder, combusts at around 464 degrees Celsius, which is 867° F. Conversely, on the hottest day ever recorded in US history, at 134° F, the interior of your car would reach between 180° – 200° F. This means that fireworks in a hot car would need additional heat of more than 600° F to spontaneously ignite. Bottom line: the best place to store fireworks is in a dry storage container in cool temperatures away from the reach of children, but a hot car or trunk will not cause your fireworks to be damaged or explode.
Are There Best Practices for Driving with Fireworks in the Car?
Yes. Consumer Reports and the Department of Transportation has a great list of best practices for moving fireworks from one location to another.
How Hot Does the Inside of a Car Get During Summer?
On the hottest days of summer, the interior of your car can reach between 180° F – 200° F. Though these temperatures are not hot enough to cause spontaneous combustion of fireworks or gasoline, extreme tempertatures can make metal surfaces like seat belt buckles, and car door handles dangerously hot. Passengers touching plastic or metal surfaces can be be burned. Extended exposure to the elevated heat in your car during the summer can also cause heatstroke, organ damage, and death in extreme circumstances.
Are Fireworks Considered Spontaneously Combustible Materials?
No. Fireworks are not in the class of materials that spontaneously combust. Spontaneous explosions belong to a classification of pyrophoric materials that ignite quickly due to atmospheric oxidation like white phosphorus. Other substances liable to spontaneous combustion are self-heating materials like drying oils, linseed oil, and alkyd enamel resins. Bottom line: though fireworks are suceptible to explosion when ignited by a flame, they are not spontaneously combustible in excessive heat up to 800° F.
At What Temperatures Do Fireworks Explode?
The explosive material in fireworks, called black gun powder, has an auto ignition temperature of 867° F, which means your fireworks will not explode even if they are stored in the Lut Desert which holds the record for having the hottest surface temperature on Earth (177.4°F).