There have been a few messages in the past about the ice surface; I thought the following article might be of interest to some. ----- From the Michigan State Blue Line Newsletter of January 1995 Newsletter Editor - Pat Morscheck Submitted to the Hockey-L list with permission from Pat Morscheck and Coach Ron Mason. KEEPING THE ICE HARD AND FAST by Tom Campbell "Something in that concrete floor makes the water freeze." Comments such as this are often heard from visitors to Munn Arena. So how do we maintain ice? The 200' x 85' floor is comprised of 6-inch think concrete. Imbedded in this surface are 255 pipes (3/4" in diameter) running the entire length and width of the ice floor. Through these pipes we pump a refrigerant known as freon 22. Freon is piped down the sides of the rink through a feeder line which runs under the dasher boards from the compressor room to a common feeding header. Freon flows from this common header to the 255 floor pipes. The freon enters the west end of the floor at a temperature of 8 degrees F. By the time it empties into a collecting header at the east end of the arena, the freon has absorbed enough heat to raise its temperature to 12 degrees F. Coach Mason likes cold, fast ice for his typically fast skating teams. Hours before each home game we set up the refrigeration system to have 10 degrees F ice at the start of the game. We also chill down the air temperature with our air handling units for the comfort of the players. The arena warms up very fast when 6,200 fans enter! There is a fine line between keeping the ice hard and fast versus it becoming too cold, brittle, and chippy. This brittleness has an adverse effect on the tempo of play up and down the ice. The main principle to remember is that to keep something very cold you have to remove as much heat as possible. It's all about transferring heat from one area and releasing it to another. There are several factors that can affect the amount of heat that is conducted to the arena floor and its adjacent concrete and superstructure. These include: (1) large crowds, (2) body heat from skaters, (3) outside air temperature and humidity, (4) arena lights, and (5) hot water from the ice resurfacer. Because of the above-mentioned factors, one of the most crucial responsibilities of our ice maintainers is to constantly monitor changes in ice temperature. A temperature sensor probe located in the concrete floor relays ice floor temperature back to a Honeywell controller. This controller senses and displays ice temperature changes down to 1/100 of a degree. As the temperature raises or lowers, the controller cycles our three 60-ton compressors on and off as needed. A worst case scenario would be a summer day in which the outside temperature is nearing 90 degrees F with high humidity. On this day we are making ice on the hour with our resurfacer putting 140 degrees F water down. Most likely, it is a rental that requires full arena lighting. It's at times like this that our temperature read-out is spinning upward and all three compressor are going full tilt. Now you can understand why we are so sensitive about keeping the arena doors closed at all times! Because of the modern and attractive appearance of Munn, many people do not realize that our facility is 20 years old. Originally the arena was designed for 6-8 months of annual operation. However, because of the tremendous demand for ice time, we currently operate at least 11 months of the year. Due to these factors, we are constantly maintaining and upgrading our facility and its system. Last year, a major project added two new condenser towers. These towers increased our heat-removing capacity by at least 40 percent. Thanks to the ongoing success of Spartan Hockey, MSU is committed to maintaining great ice and an attractive and comfortable facility for years to come. ----- MUNN ARENA FACTS: Year Built : 1974 Ice Surface : 200' x 85' Seating Capacity: 6170 Single Game Attendance Record: 6,902 (vs. BGSU - 2-6-87) Series Attendance Record : 13,780 (vs. LSSU - 2-13/14-87) Season Attendance Record : 157,567 (1975-76)