HAZARDS OF DRY ICE
Contact Hazard: At -109 °F (-79 °C), skin contact with dry ice is can lead to severe frostbite; skin cells freeze and become damaged very quickly.
Asphyxiation Hazard: Dry ice will sublime (change from solid to gas) at any temperature above -109 °F. This releases potentially substantial volumes of CO2 (1 pound solid = 250 liters gas), which can displace oxygen quickly in the air around the dry ice, causing difficulty breathing, loss of consciousness and death. This is especially of concern in nonventilated or confined spaces.
Explosion Hazard: Due to the rapid emission of large volumes of CO2 gas, any dry ice that is stored in a closed container can pressurize the container. Given enough time at normal room temperature, such a container may explode if the gas is not able to escape.