Dichlorodifluoromethane and all others in its class of chlorine compounds were eliminated in the world R12 being the one most people are familiar with. It was replaced with chlorine free R134 due to Dichlorodifluoromethane nasty habit of floating into the sky where UV light broke its chemical chains releasing the chlorine molecules which have a habit of binding to ozone or O3 gas forming chlorine dioxide itself a nasty substance but more importantly by consuming ozone it removed it from the stratosphere letting more in to the surface this us and for plants and people. The world is a much better place for the banning of the chlorocarbons.
The mass of a mole of Dichlorodifluoromethane is 120.91gm.
The (average) mass of a mole of dry air is is 28.97 gm.
One mole of gas occupies exactly the same volume, 22.4 liters, regardless of the composition of the gas molecules.
Bit hard to see how it can have the "habit of floating into the sky," since its density is more than four times that of air.
In the city I live near, four men died back in the 1980s at a company that makes refrigeration equipment. Two were down in a slitter machine pit. Someone vented some R-12 fifty or sixty feet from where they were working. The gas flowed into the pit, knocking out both men. Another worker looked down, saw they were unconscious, called a supervisor, and went down to rescue them. He lost consciousness too.
When the supervisor arrived, saw the three of them lying on the floor at the bottom of the pit, he immediately hit an alarm and climbed down to help them. He also lost consciousness, in a few seconds.
By the time a qualified rescue team could get to the scene, all four were deceased.