Dry ice is solid Carbon Dioxide, it is made by reducing the pressure and the temperature of liquid carbon dioxide in a controlled way so that it converts into the " snow " form of the solid state, which is then made into various shapes and sizes.
Characteristics of dry ice.
Dry ice has a number of characteristics which make it a good choice as a refrigerant in the chemical, biological, medical and food industries.
It sublimes into Carbon Dioxide gas without leaving a residue
It appears as a translucent white solid
It is non flammable.
It creates an atmosphere which is inert and which has specified exposure limits under the COSHH regulations.
One of the best known applications of dry
ice is in the field of special effects where a mist can be produced to create visually
exciting moods for theatre productions, in clubs or at presentations.
Always store dry ice in a properly
Keep the lid or cover of the container closed when not in use.
Do not store dry ice in airtight containers.
Do not expose dry ice to high ambient temperatures unnecessary as this increases the sublimation rate and thereby the risk of high carbon dioxide atmospheres.
Do not store dry ice in cellars or unventilated rooms.
Ensure adequate low level ventilation wherever dry ice is stored.
The use of monitoring and warning devices for dangerous atmospheres is strongly recommended.
Do not transport dry ice in the cab of a
truck or the passenger compartment of a car.
Preferably use dry ice in vehicles where the driver's cab is isolated from the load compartment.
Secure the load compartment door in the open position before entering.
Doors should be capable of being opened from the inside.
Always ensure that there is adequate ventilation before entering the load compartment.
Always carry a carbon Dioxide ( SOLID ) safety data sheet in the cab of any vehicle which is carrying dry ice.
Before handling and using dry ice, you must understand it's properties, the hazards arising and the actions to take in an emergency.
What follows is general information on the
composition of dry ice and advice on it's safe handling, storage and transport.
It should be read in conjunction with the individual safety data sheets which are available from BOC.
The Properties of Dry Ice.
Dry Ice is solid Carbon Dioxide, the
chemical formular for which is CO2. Carbon Dioxide in present in the air ( 0.03% ) and is
non flammable. colourless gas with a slightly pungent odour which is only detectable at
high concentrations. It does not support life and is an asphyxiant, being one and a half
times heavier than air.
Dry Ice appears as a translucent white solid and is unusual in that it sublimes from the solid state directly into a gas without passing through a liquid phase.
10kg of Dry Ice sublimes into about 5.4 cubic meters of Carbon Dioxide gas. Carbon Dioxide is notifiable under the control of substances hazardous to health and has an exposure limits as follows: STEL 1.5 % ; LTEL 0.5 %
Carbon Dioxide is heavier than air and will concentrate low down, aspecially when cold. As it warms it will mix into the air.
The temperature of Dry Ice is -78 0C
Before using Dry Ice in any area, establish the risks involved - especially concerning the creation of atmospheres with high concentrations of Carbon Dioxide near the ground.
1. Only experienced and properly instructed people should handle Dry Ice.
2. DO NOT remove or deface any product labels.
3. Know and understand the properties of Dry Ice/
4. Establish plans for an emergency.
5. Use Carbon Dioxide monitors to warn of problems.
6. NEVER play games with Dry Ice.
7. Ensure that children only use Dry Ice under supervision.
8. Always wear eye protection and heavy insulated gloves. NEVER HANDLE DRY ICE WITH YOUR BARE HANDS - it can cause frostbite.
9. Dispose of Dry Ice in a well ventilated area away from the public.
10. Take care when carrying packages of
Dry Ice and adopt Kinetic handling techniques.
Dry Ice -78oC