Dry ice and water ice have similar applications, but their physical properties affect how they are used and handled. Here are a few simple differences between the two that could help you choose the best ice for the job!
Water ice is made up of (you guessed it) water. When it warms, the frozen ice melts, leaving a puddle. Dry ice is made up of carbon dioxide (CO2). When it warms, the solid CO2 sublimates into the gaseous form of CO2. Dry ice skips the liquid phase entirely, leaving virtually no mess to clean.
Dry ice maintains a temperature of -109.3°F, giving it three times the cooling energy per volume than water ice. What does this mean? Dry ice stays colder and lasts longer than water ice, and water ice will melt much faster and need to be replaced to keep items cool frequently.
When not in use, water ice must be stored in a refrigerated unit or risk it rapidly melting before use. Dry ice should be stored in a well-insulated container to slow sublimation; no refrigeration is necessary. Dry ice should be kept in a well-ventilated area to ensure the CO2 created from sublimation does not displace the oxygen in the air.
Water ice may feel cold at the touch, but it does not require any additional supplies to handle. When handling dry ice, thick gloves or tongs must be used to avoid the risk of frostbite. Although dry ice can be food-grade, it is never recommended to ingest dry ice. Review safety guidelines from the Compressed Gas Association (CGA) before handling dry ice.