Before handling and using dry ice ensure that you understand its properties, potential hazards and actions to take in an emergency.
Properties.
- Dry ice is solid carbon dioxide. Chemical formula CO².
- Dry ice appears as a translucent white solid which at normal temperatures sublimes from the solid state directly into a gas without passing through a liquid phase.
- Non flammable, asphyxiant.
- Colourless gas with a slightly pungent odour which is only detectable in high concentrations.
Hazards.
- Asphyxiant – in high concentrations sublimed vapour may cause asphyxiation. 10kg of dry ice sublimes into about 5.4m³ of carbon dioxide gas.
- Extreme cold – contact with product can cause cold burns or frostbite. The temperature of dry ice is -78° C.
Tips
- Do not handle dry ice with bare hands. It can cause severe cold burns and frostbite.
- Before using dry ice in any area, establish the risks involved. Ensure you consider the potential for the creation of atmospheres with a high concentration of carbon dioxide near the ground.
- Only experienced and properly instructed people should handle dry ice.
- Do not remove or deface any product labels.
- Know and understand the properties of dry ice.
- Establish plans of emergency.
- Always seek professional advice on suitable ventilation systems. Use carbon dioxide monitors to warn of problems.
- Never play games with dry ice.
- Always keep children and pets away from dry ice.
- Water on CO² increases sublimation with a corresponding higher risk of asphyxiation.
- Always wear eye protection and heavy insulated gloves suitable for extreme cold temperature of dry ice.
- Dispose of dry ice in a well ventilated area away from the public. Do not discharge into any place where its accumulation could be dangerous.
- Take care when carrying packages of dry ice.
Storage
Many factors can affect the rate at which dry ice sublimes from its solid state into gaseous carbon dioxide. These include ambient temperature and humidity, the quality of the storage container, the number of times the container is opened and closed. The better the insulation, the slower the sublimation rate and the longer the quality of the product will be maintained.
- Always store dry ice in a properly designed container.
- Keep the container lid closed when not in use.
- Always secure the container lid open before reaching in to unload the product. Avoid leaning into the container for longer than necessary.
- Do not store dry ice in any gas tight container. Within large containers, gas atmospheres will have built up.
- Do not expose dry ice to high ambient temperatures unnecessarily as this increases the sublimation rate.
- Do not store in cellars or unventilated rooms.
- Ensure adequate low level ventilation wherever dry ice is stored.
Transportation
- Avoid transporting dry ice in the cab of a truck or the passenger compartment of a car. If this is not possible the load should be well insulated and adequate ventilation maintained.
- It is preferable to transport dry ice in vehicles where the driver’s cab is isolated from the load compartment.
- Always ensure there is adequate ventilation during transportation and before entering the load compartment.
- Always unload the product as soon as possible at the end of the journey and move it to a suitable storage location.
