The ammonia would be in a closed loop system. By only freezing water to make ice and to keep an icebox cool (the icebox and where you freeze the water are two

The ammonia would be in a closed loop system. By only freezing water to make ice and to keep an icebox cool (the icebox and where you freeze the water are two seperate physical locations), you reduce the risk of any ammonia related injury or contamination. You would just have a bunch of 1 gallon jugs of water you freeze and swap out between the icebox and the freezer). Like the olds days! http://en.wikipedia.org/wiki/Icebox http://en.wikipedia.org/wiki/Icebox