4How Damaging Is Halon to the Ozone Layer?
A compound's ability to destroy ozone depends on many factors, including the amount of chlorine and/or bromine that it contains. To aid in comparing compounds, scientists have developed a relative scale called the ozone depletion potential (ODP). Common refrigerants, like those found in refrigerators and in automobile air conditioners, have been assigned the value 1 as a reference. Halon 1301 has the value between 10 and 16, meaning it has 10-16 times the more potential for destroying the ozone layer.
Halon use worldwide is significantly less than that of CFCs, so even though it is more damaging to the ozone layer, there is not as much of it released into the atmosphere. In fact, it is estimated that overall Halon accounts for less than 20% of ozone depletion.