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Carbon dioxide

CO2, dry ice or cardice (solid form)

SPRI Emission Reporting Threshold
10,000,000 Kg/yr Pollutant Emissions to Air
This sheet is a generic summary, designed to give the reader a basic level of background information about the substance in question. Great care has been taken to represent as effectively and correctly as possible the broad range of (not necessarily consistent) information which is available from a variety of sources. The reader must accept therefore that this sheet has no legal status and cannot be relied upon in any legal proceedings. SEPA disclaims any responsibility or liability whatsoever for errors and omissions in this sheet.
What is it?
Carbon dioxide occurs naturally in the earth's atmosphere as a colourless, odourless gas.
What is it used for?
The main uses of carbon dioxide are as a coolant, a fire extinguishing gas, as the bubbles in fizzy drinks and (when solid) to produce smoke effects.
Where does it come from?
The main source of carbon dioxide into the atmosphere is from living organisms breathing it out. Similar quantities are absorbed by plants. Other (much smaller) natural sources are forest fires and volcanoes. The burning of fossil fuels (coal, oil and natural gas) for industrial, domestic and transport purposes releases significant, though relatively smaller, amounts.
How might it affect the environment?
On a local scale, increased levels of carbon dioxide are unlikely to cause adverse environmental impacts. Its main impact is on a global scale: It is one of the main "greenhouse gases" contributing to global warming and is used as a reference against which to rate the "global warming potential" of other greenhouse gases.
How might exposure to it affect human health?
At normal environmental concentrations, carbon dioxide has no impacts on human health. At extremely high (artificial) concentrations in an enclosed space the reduction in oxygen levels could lead to suffocation.
What steps are being taken to limit the potential impacts?
The United Nations Framework Convention on Climate Change (Kyoto Protocol, 1997) introduced measures (such as taxes on fossil fuels) designed to achieve reduction of greenhouse gas releases (including carbon dioxide). Amongst the other signaturies from around the world, the UK government (including Scotland) is committed to reaching targets of reduction of carbon dioxide emissions by 2008-2012.