Halloween parties are great fun, but it can be a challenge to create just the right spooky-yet-festive atmosphere for your party. In addition to a treasure trove of Halloween decorations, pumpkins, and tasty treats, Halloween fog is a very cool way to go the extra mile. There are several ways to do this, ranging from options almost free to very expensive, very simple to incredibly complex. Here are two ways you can enhance your party with Halloween fog.

Dry Ice. Dry ice is solidified carbon dioxide that, upon melting, turns to gas. This white fog is not the invisible CO2 gas, but rather the condensed water vapor mixed in with carbon dioxide. The extreme cold causes the water vapor to condense into clouds. The heavy fog, carried by the CO2, will settle to the bottom of a container and can then be poured. You can produce enough low lying fog to fill a medium sized room with about a pound of dry ice.

This gas can cause headaches and drowsiness if inhaled over long periods of time, so do not allow anyone to lie down in this fog. Babies or pets should also stay away. Breathing should happen above the level of the fog. Dry ice is also dangerous to touch with bare hands. Much colder than regular ice, dry ice can cause frostbite in seconds when in contact with skin. Wear gloves or use tongs when handling it. It should not be eaten or placed into the mouth, and children should be kept away from it.

Dry ice can be used in many ways to create a nice foggy atmosphere. Do have adequate ventilation, however, as it needs to be allowed to circulate as it melts and becomes fog. You can put a piece into a big pot, add warm or hot water and let the fog pour out as it melts. You can pour hot or boiling water on top of it to accelerate the melting and, thus, the fog output. Of course, faster melting means it won’t last as long, but it will create a higher density and amount of fog. A small fan can disperse the fog around the room. Don’t add it to drinks, because it should not be eaten.