A cool history of coolants

How we keep ourselves and our stuff (like food) cool is a lesson in ingenuity, innovation and a little like Whack-A-Mole. Every time scientists developed the next best thing, it caused problems somewhere else. 

When the scientists started looking at ways to get air colder than a fan, they focused on vapor compression systems. Essentially, this is the air conditioner you have now in your car and in your house. It uses circulating liquid refrigerant to remove heat from a space. 

The first refrigerants were things like ammonia and carbon dioxide, which were effective but, you know, toxic. 

In 1928, Freon was developed. Freon was the trade name for a type of coolant called a chlorofluorocarbon. .