When it came time to launch their new refrigerant, CFCs, in 1929, Kettering and Midgley aimed to avoid the uproar of the Loony Gas scandal. Their biggest concern was that CFCs contained fluorine, which was known to be toxic and was, in fact, a common ingredient in insecticides. They sought to demonstrate that fluorine was rendered inert when it was bound up in CFC compounds. For an audience of reporters and fellow scientists, Midgley gave another daring performance, this time inhaling quantities of gaseous CFCs. He then turned and blew out a candle, "proving" that CFCs were neither toxic nor flammable.

What Kettering and Midgley didn't realize was that the real danger of CFCs comes not from fluorine but from chlorine, and that the risk was not to people who directly handled CFCs but to a thin band of molecules 15 miles above the earth.

The ozone layer itself was then barely known or understood. Not until 1931, three years after the invention of CFCs, would British geophysicist Sydney Chapman delineate the workings of the ozone layer.

OZONE, containing three atoms of oxygen (an oxygen molecule has two), is a form of oxygen present in trace amounts throughout our atmosphere. In the stratosphere, ozone absorbs incoming rays of shortwave ultraviolet light from the sun that would be deadly to all living things if they were to reach earth. As Chapman found, ozone is created and destroyed by sunlight in an unending cycle, but a balance is always present in the stratosphere.