Using dry ice (solid carbon dioxide // carbon dioxide = CO2) can cause serious burn wounds!!! Be extremely carefully if you need to handle it. Never touch it directly (although you can get away with it if you know what you're doing).
Dry ice has a surface temperature of around -80°C. The extreme cold will give you burn wounds. If you keep it under pressure and it explodes (dry ice bombs) it can not only cause severe wounds, blindness (small parts shooting in your eyes; doesn't even need to be at high velocity; the freezing cold is enough), and even damage to your ears because of the intensive explosion.
NEVER EVER lick, taste or even swallow it, even a tiny amount will get you in hospital and give you permanent wounds. This includes putting dry ice in drinks! Or accidently getting dry ice in your eyes...
---
You can get dry ice in many forms.
The liquid kind is as good as impossible to get (liquid CO2). Also don't confuse the liquid form with liquid nitrogen (which boils at avg. -200 degrees!) and often seen to flash-freeze stuff.
Dry ice is a solid and sold as big chuncks/blocks, crunched in smaller chunks or as small kind of marbles.
You can buy it easly from specialized companies, welding shops, sometimes ice cream places, chemical supply houses, etc.
Also don't confuse the smoke you often see in theater and stuff with the smoke from dry ice. Although dry ice is often used for it, it also is a specific kind of very low hanging, crawline, dense and intense white smoke. In many plays you also see "not so dense" smoke, the cheaper variant. This is caused by lowering the temperature of the smoke which comes from ordinary smoke machines (used on parties for example).
I handled kilo's of dry ice on a daily basis for almost a year (used for FX in a big musical play). And still handle it now and again (again for theater related stuff).
I strongly suggest NOT to play with dry ice, especially not experimenting with dry ice bombs. It is as dangerous as playing/experimenting with fireworks!!!
To proof that this is not as safe as you might think search the net for the accidents which can happen extremely quickly.
eg:
quote:
Originally posted by Angela_Hinkhouse
I was reading your web page about the accident involving the dry ice and the loss of the woman's sight. On July 3, 1999 a similar accident happened in my family. My then three year old son was seriously injured, He lost one of his eyes, his right thumb was 75% severed and broken, his left thumb was 50% severed and he had a gash about 4 inches long on his stomach. I had also never heard of this and was mortified. My son is now doing wonderful and we are very vocal about it to let people know what can happen with what I found out after the fact to be called "dry ice bombs".
/ 
