1.   Ozone in the stratosphere is a gas that is essential in protecting humans from carcinogenic ultraviolet radiation from the sun.

2.   Ozone in the stratosphere is essential to help protect people from carcinogenic ultraviolet radiation from the sun.

3.   Ozone in the upper atmosphere is a gas that protects humans from carcinogenic ultraviolet radiation from the sun.

4.   Stratospheric ozone is essential in protecting humans from carcinogenic ultraviolet solar radiation.