Ozone present in the troposphere is also called as bad ozone. It is also a
green house gas. It is the major constituent of the urban smog.
No ozone is not always harmful. the ozone at stratosphreric level is good.
Halons are harmful for ozone. They also react with ozone to deplete it.
Ozone in troposphere is harmful. It acts as a pollutant.
The harmful effects of ozone are seen at ground level. Ozone acts as a pollutant there.
Ozone layer cannot be harmful. It protects us from harmful UV rays of the sun.
The ozone is harmful not at stratosphere. It is harmful at some layer. Te layer is troposphere.
Ozone is harmful at ground level. It acts as a pollutant.
It is harmful at ozone layer. It is because this leads to depletion of ozone.
See "How can ozone be harmful and helpful?" in the "Related questions" section below.
Ozone at land is harmful. It acts as a pollutant.
The ozone layer is most harmful in the stratosphere, the second layer of the atmosphere. It helps to protect Earth by absorbing harmful ultraviolet radiation from the sun, but ground-level ozone can be harmful to human health as a pollutant in the troposphere.
Ozone in upper atmosphere is not harmful. No harmful effects are associated with it.