Emissions of halon-1211, a fire retardant, are increasing at the rate of approximately 200 tonnes per year, based on measurements in the atmosphere made in the Australian island state of Tasmania. The substance was used in fire extinguishers and for flooding fires. In fact, emissions have since risen by about 25 percent, Dr. Fraser says.
Current emissions make it the most damaging of the halons.
Halons are now responsible for about 20 percent of global ozone destruction. China is responsible for about 90 percent of the world's production of halon-1211. Under the Montreal Protocol, designed to protect the ozone layer, developing countries such as China have until the year 2010 before they must completely phase out halon production. Montreal Protocol calculations based on production data indicate that halon levels in the air will stabilise during the next few years. Unfortunately, growth of halon-1211 is likely to delay this stabilisation by years.