To start, let’s define what we mean by low temperature refrigeration. The term low temperature refers to the cooler side of a general temperature range. In air conditioning, chilled water or glycol at 32°F (0°C) would be considered low. In industrial refrigeration, blast freezing at –50°F to –60°F (–45°C to –50°C) is considered low. In the realm of cryogenics, temperatures approaching –460°F or 0°R (–273°C or 0 K) are suitably designated low. But none of these belong in the category discussed in this article.