From a glance, Industrial Refrigeration (IR) seems to be an easy sector regarding low GWP refrigerants, but we still see potential pitfalls as well as room for innovation. NH3 (ammonia) has been the preferred refrigerant in IR due to its excellent efficiency and it continues to be used as demands for sustainable refrigerants increase. However, safety concerns may potentially limit the success of NH3 as it is toxic; there have been some severe accidents in the last decade, which taught us, an industry, some important lessons such as avoiding large charges and carefully planning the location of larger plants. This has led IR to find new, innovative ways to reduce charge sizes. One way to decrease charge size while increasing efficiency is to combine NH3 with CO2: CO2 takes on the role of thermal carrier and is circulated inside the larger storage facilities.