Which statement about ozone depletion potential (ODP) is correct?

Which statement about ozone depletion potential (ODP) is correct?

• A. A measure of a gas's ability to trap heat in the atmosphere
• B. The rate of ozone generation in the upper atmosphere
• C. The amount of ozone remaining after release
• D. A relative measure of a substance's potential to destroy stratospheric ozone compared to CFC-11

Answer: (D)

Ozone depletion potential is a relative index that measures how much a substance can destroy stratospheric ozone, compared to a reference chemical (CFC-11) whose ozone-depleting potential is set to 1.0. It captures how effectively a molecule releases ozone-destroying chlorine or bromine radicals in the atmosphere, and how much ozone would be depleted per unit mass under the defined conditions. The key is that it’s a comparison, not an absolute amount of ozone destroyed, and it reflects chemical behavior in the stratosphere rather than heat-trapping or the amount of ozone remaining. In practice, a chemical with a higher ODP poses a greater threat to the ozone layer than CFC-11 per unit mass, while substances with very low or zero ODP either don’t release those radicals or do so only minimally.

Ozone depletion potential is a relative index that measures how much a substance can destroy stratospheric ozone, compared to a reference chemical (CFC-11) whose ozone-depleting potential is set to 1.0. It captures how effectively a molecule releases ozone-destroying chlorine or bromine radicals in the atmosphere, and how much ozone would be depleted per unit mass under the defined conditions. The key is that it’s a comparison, not an absolute amount of ozone destroyed, and it reflects chemical behavior in the stratosphere rather than heat-trapping or the amount of ozone remaining. In practice, a chemical with a higher ODP poses a greater threat to the ozone layer than CFC-11 per unit mass, while substances with very low or zero ODP either don’t release those radicals or do so only minimally.