For information relating to specific products, consult the relevant Safety Data Sheet.
Dry ice is the common name given to solid carbon. Dry ice converts to carbon dioxide gas at -78°C. Whilst not strictly a cryogenic substance, dry ice is also routinely used as a cooling agent in laboratories.
Cryogenic substances, such as liquid nitrogen, are used to produce very low temperatures and have a boiling point of -153°C. They are often used in medical and research fields to preserve biological material. Most cryogenic substances are odourless, colourless, and tasteless. They have a liquid state when kept at very low temperatures, create a visible fog when exposed to air and turn to gas at room temperature.
Dry ice and cryogenic substances can remove oxygen from the environment. If stored in confined areas or rooms without ventilation, a leak could result in a lack of oxygen within that room.
Dry ice and cryogenic substances should never be stored in sealed, air tight containers at temperatures above their boiling points. As the substance warms, it reverts to its gaseous state, causing expansion and a build-up of pressure within the container. This pressure could result in an explosion.
Due to the very low temperatures of these substances, direct contact with the skin can cause severe frostbite and permanent tissue damage. Other hazards include fire, explosion, pressure build-up and asphyxiation.
When working with cryogenic substances:
- handle substances with care to avoid skin burns and frostbite
- only use in a well ventilated area
- always wear appropriate PPE
- always use proper containers designed for the transport and use of cryogenic liquids, such as pressurised containers that are protected with multiple pressure relief devices
- regularly check containers and pressure relief valves for signs of wear
- do not use if any defects are detected
- use tongs to withdraw objects immersed in a cryogenic liquid
- do not fill containers to more than 80% of capacity.
PPE should include:
- safety glasses
- a full face shield
- cryogenically rated, loose-fitting gloves
- gloves should be loose fitting so that they can be quickly removed
- cryogenic gloves are for indirect or splash protection only, they are not designed to protect against immersion into cryogenic liquids
- long-sleeved shirt and pants
- safety shoes.
Risk control measures
Any business that handles or stores hazardous substances must develop, implement and maintain safe systems of work, This includes:
- conducting a comprehensive risk assessment prior to the use, handling and storage of any hazardous substances
- implementing appropriate controls to eliminate or minimise the risks associated with the use, handling and storage of hazardous substances
- providing workers with adequate information, training and instruction in relation to the safe use, handling and storage of hazardous substances, the associated risks and the control measures implemented to control those risks.