It’s NBA and NHL postseason again! While some cities have both of their sports teams in playoffs, they have to go through with the process of converting basketball court to ice rinks. For example, the Chicago Bulls and Blackhawks are both in the playoff and they both share the same home court. Another example would be the LA Clippers and Kings. The crew would have to tear the court down and putting the ice on. It amazes me on how they can do it regularly and everything works like perfect. The science behind on how to make ice is the same that works for refrigeration. You can learn more about the chemical engineering about refrigeration by clicking here.
However, there’s one major difference in making an ice rink. First of all, an ice rink is huge, and also, the refrigerant cools brinewater instead of cooling the ice directly. Brinewater is a Calcium-Chloride solution, it is continuously pumped through the pipes underneath the ice. The pipes are embedded in the ice-bearing concrete slab. The ice-bearing slab sits between the skating surface and a layer of insulation. The insulation allows the ice to expand and shrink as time moves on. The brinewater helps keep the ice-bearing slab’s temperature just below 32 F so that the water spread onto it can freeze. Although it happens not very often, basketball players sometimes would slip and fall by the sideline and they complain that they felt an icy spot on the court. This is maybe because the ice is not actually melted. Underneath the court that is a concrete floor embedded with temperature control mechanisms. The ice remains frozen for the duration. When it comes time to switch to basketball, workers lay interlocking mats made from rubber or a fiberglass-foam composite over the ice.
Below is a time lapse of how the switch over is done in real life!