Hazards of Dry Ice
Dry ice is the solid form of carbon dioxide. It is non-combustible and is available in flakes, pellets, or block form. Dry ice will sublime (vaporizes directly to the gas state) at a temperature of -78.5 C (-109.3 F) or higher.
Dry ice is commonly used to cool reactions or to ship biological specimens.
Dry ice is considered hazardous for three reasons:
- Explosion hazard: dry ice releases a large volume of carbon dioxide gas as it sublimates. If packaged in a container that does not allow for release of the gas, it may explode, causing personal injury or property damage.
- Suffocation hazard: a large volume of carbon dioxide gas emitted in a confined space, or other unventilated area (e.g. cold room) may create an oxygen deficient atmosphere.
- Contact hazard: dry ice is a cryogenic material that causes severe frostbite upon contact with skin.
Handling Dry Ice Safely
- Dry ice must be stored in a well-ventilated location. NEVER store dry ice in a cold room, warm room, or storage closet unless adequate supply ventilation is provided.
- Dry ice cannot be stored in any type of tightly sealed device such as an ultra-low freezer, plastic/glass container, or other enclosed space. Store dry ice in a stryofoam chest, insulated cooler or a special cooler designed for the the storage of dry ice (i.e. allows for the release of carbon dioxide gas).
- NEVER handle dry ice with your bare hands. Always wear thermal gloves to reduce risk of thermal burns to the skin.
- Dispose of unneeded dry ice by:
- Letting the unused portion sublimate in a well-ventilated area.
- NEVER dispose of dry ice in a sink, toilet or other device. Such action can destroy the structure because of the temperature difference.
- NEVER dispose of dry ice in the trash or garbage.
- NEVER leave unneeded dry ice in hallways or other public areas.
- Do not place dry ice on a tiled or solid surface countertop as the extreme cold will cause damage.
- Never transport hazardous materials in your personal vehicle. If you transport dry ice in an approved university vehicle, it must be stored in the trunk or location apart from the driver.