How do I generate fake steam in a way that will not scald someone?

Question

I need to find a way to make steam come out of the ears of a costume, but obviously real steam would be too dangerous. I'm looking for the way they accomplish the effect in movies and such. Things such as dry ice make a gas heavier than air however, so those will not work.

Answer 1

Blow talcum (baby) powder out of a tube.

A fake smoke cloud can be made using a funnel and a lenght of 1/2 in dia tubing. Attach the tube to the neck of the funnel.  Take som electrical tape and stretch two pieces across the funnel top to make a cross shape. The tape helps to difuse the talcum powder.  Add power to the funnel then blow through the tube.

You can use a similar process without the funnel.

An other option is to use smoke tubes (see link) . THese are used in the HVAC industry to check air flows. THere are several types  which used either a fine powder or a chemical reaction with humidity to produce a white smoke.

Answer 2

Perhaps a pizeo-electric water vaporizer might work. It is an electric device which uses a vibrating plastic film to break water up into such tiny droplets it appears as a thick, foggy mist. The only drawback is the device is somewhat bulky, so the costume needs rather large ears. Also such a device would have to be battery powered.

Another possibility is smoke. Smoke generators blow a current of air across a smoldering wick saturated in oil. The smoke is lighter than air and will rise.

Some fireworks consist of smoke bombs. They generate a bit too much smoke for a costume, but the bomb can be carefully cut into smaller pieces. Properly designed, a simple electric fuse could ignite the piece of smokebomb. A fan driven air current could be used to blow the smoke out of the ears. This might take a bit of tinkering to perfect, but the effect ought to be quite entertaining of done right.

One quite dramatic way to make a thick cloud of white smoke is the reaction of hydrochloric acid and ammonia vapor. They mix to form a dense fog of ammonium chloride crystals. The crystals are harmless, but the ammonia and acid are quite corrosive. They also smell rather bad as well, especially the ammonia.

Finally, the most dramatic smoke effect might be the semi-explosive nitrogen tri-iodide reaction. If pure iodine crystals are added to a concentrated solution of ammonia, a solution of nitrogen triodide will form (NI3). The solution can be soaked into paper and carefully dried. Once dry, any shock will cause the NI3 to discintegrate into a dramatic purple puff of iodine gas. Iodine itself is a semi-toxic disinfectant, but not too bad in small concentrations. Like chlorine, it will probably bleach anything it soaks into.

Good luck!