"APPLICATIONS Most ice surfaces are used for a variety of sports@ although some are constructed for specific purposes and are of specific dimensions. Usual rink sizes include the following: Hockey. The accepted North American hockey rink size is 85 by 200 ft. Radius corners of 28 ft are recommended by professional and amateur rules. The Olympic and international hockey rink size is 100 by 200 ft@ with 28 ft radius corners. Many rinks are considered adequate with dimensions of 85 by 185 ft@ 80 by 180 ft@ and 70 by 170 ft. In substandard size rinks@ a corner radius of not less than 20 ft should be provided to allow use of mechanical resurfacing equipment. Curling. Regulation surface for this sport is 14 by 146 ft; however@ the width of the ice sheet is often increased to allow space for installation of dividers between the sheets@ particularly at the circles. Most curling rinks are laid out with ice sheets measuring 15 by 150 ft. Figure Skating. School or compulsory figures are generally done on a ""patch"" measuring approximately 16 by 40 ft. Freestyle and dance routines generally require an area of 60 by 120 ft or more. Speed Skating. Indoor speed skating has traditionally been performed on hockey-sized rinks. The Olympic-sized outdoor speed-skating track is a 1400 ft oval@ 35 ft wide with 392 ft straightaways and curves with an inner radius of 87.5 ft. Most speed-skating ovals were originally constructed outdoors@ although some are now constructed indoors. Recreational Skating. Recreational skating can be done on any size or shape rink@ as long as it can be efficiently resurfaced. Generally@ 25 to 30 ft2 is allowed for each person actually skating. This ratio may vary for large numbers of beginner skaters. An 85 by 200 ft hockey rink with 28 ft radius corners has an area of 16@327 ft2 and will accommodate a mixed group of about 650 skaters. Public Arenas@ Auditoriums@ and Coliseums. Public arenas@ auditoriums@ field houses@ etc.@ are designed primarily for spectator events. They are used for ice sports@ ice shows@ and recreational skating@ as well as for non-ice events@ such as basketball@ boxing@ tennis@ conventions@ exhibits@ circuses@ rodeos@ tractor events@ and stock shows. The refrigeration system can be designed so that@ with adequate personnel@ the ice surface can be produced within 12 to 16 h. However@ general practice is to leave the ice sheet in place and to hold other events on an insulated floor placed on the ice. This approach saves significant time@ labor@ and energy. Bobsled-Luge Tracks. The bobsled-luge track usually incorporates steel piping embedded in the track and fed by an ammonia liquid recirculation system. Approximately 280@000 to 315@000 ft of piping is required for an Olympic-sized track. The total refrigerated surface is 90@000 to 105@000 ft2. Refrigeration plant capacities in the range of 1100 to 1400 tons are required@ depending on ambient design conditions@ wind@ and sun loads. The ammonia charge can exceed 200@000 lb. Because elevation changes are significant@ care must be used in placing liquid recirculators@ selecting ammonia pumps@ and circuiting floor piping."