Come Autumn time, dry ice is a favorite special effect for Halloween parties and moody basement shows. But is it safe?
Dry ice isn’t the ice made out of frozen water that you pull out of your freezer and plop into cool drinks. It’s actually carbon dioxide (CO2), cooled and solidified at about -79 degrees Celsius, or about -110 degrees Fahrenheit. Carbon dioxide itself is not dangerous to us; in fact, we create a lot of it. Animals, including humans, breathe carbon dioxide out into the atmosphere where plants and algae can turn it back into oxygen for us to breathe.
There is a recent case still developing where a man transporting strawberries in dry ice was found unresponsive in his delivery truck in Missouri. The claim? That the inadequate packaging of the dry ice allowed “noxious fumes” to seep into the truck’s air and kill the poor driver. Could the carbon dioxide coming off the dry ice really have killed this trucker?
The answer is… maybe. Again, that case is still developing. But dry ice’s output of carbon dioxide actually can be toxic in high concentrations. Dry ice sublimes, meaning it goes from a solid state directly to gas state when warm enough (hence the cool foggy effect it creates) instead of melting into a liquid, like traditional ice would. Although we can breathe small amounts of carbon dioxide in all air with no problem, we need to breathe a good amount of oxygen with it. Oxygen is what keeps our brains going, not CO2. At 3-5% concentrations of CO2 in the air, you might experience rapid breathing or headaches. At 7-12%, the breathing issues and headaches will worsen, and you might even fall unconscious. Levels higher than 12% can cause anyone breathing that air to suffocate. There’s not enough oxygen.
Presumably, the trucker passed away because his sealed truck held too high a concentration of carbon dioxide sublimating from the strawberry packaging. The catch? It’s difficult to totally seal a container that carries dry ice, as dry ice can be pressurized from all the gas coming off it and cause the container to explode.
So are you at risk for dry ice/CO2 suffocation? Probably not. If you decide to use dry ice for your next show or party’s foggy and smoky effect, just make sure the area is well ventilated. If you’re in a well-ventilated area where oxygen can flow in freely and CO2 can escape, you are in no danger of suffocation.
Another minor dry ice risk? It’s safe to pop in drinks and food to make cool fizzy effects, it’s just like carbonating a soda. BUT, medium to large dry ice chunks can be extremely dangerous to swallow, and you also don’t want to directly handle dry ice with bare skin. It’s extremely cold, so it can easily cause tissue damage.
Overall, go ahead and use dry ice to spook-ify your next bash this fall — just be smart about it.