Ever wonder if all that stuff you learned, and just as quickly forgot, in high school chemistry class might come in handy?
Consider Gary Hale.
With no more esoteric lore than students get out of such a class, the operations manager of the Baltimore Arena knows how to make ice on a grand scale, enough to fill a hockey rink.
When asked how much water it takes to make an ice floor, Hale pauses, then says: "Lemme have a pencil." In less time than it would take to use a calculator, he works it out on paper. Clearly, he hasn't forgotten his high school math, either.
Turning the concrete floor of the arena into an 85-by-195-foot ice rink requires about 11,320 gallons of water per inch thickness of ice.
The chemistry of the ice system is elementary: When you dissolve a salt in water, it lowers the freezing temperature of the water. That's why the Atlantic Ocean doesn't turn into a skating rink every winter -- and why the floor of the Baltimore Arena does.
The freezing solution, which runs through pipes under the floor to make it cold before water is applied, is nothing more than water mixed with calcium chloride into a thick solution of brine that remains liquid well below the freezing temperature of plain water. Some systems use ethylene glycol, the active ingredient in automobile antifreeze, but it's more expensive, Hale says.
For this week's presentation of "Starlight Express," an Andrew Lloyd Webber musical on roller skates that has been adapted for ice skaters, the arena's ice plant went into action at 7 a.m. on a Monday, a week ago, just after the previous weekend's professional wrestlers had gathered up their mats and counted the gate receipts.
The plant is a trio of industrial-strength chillers, each with four compressors, that chug away in the basement of the arena. Each of the dozen compressors, covered with frost, is about the size of a foot locker. They're quite sleek, having been installed just three years ago as part of an overhaul of the entire ice-making system.
The previous system had lasted 30 years, since the arena opened in 1962. You can expect an ice plant to run 20 to 25 years, Hale says, so the arena's had far outlasted its life expectancy.
Since 1994, the arena has replaced the chillers (the new ones are computer-controlled), the underground pipes and the dashers, big sheets of wallboard that frame the rink. This summer, the last component of the system was replaced when the arena installed a new concrete floor. The cost of the entire renovation was $749,000.
"To freeze the floor, we set the plant at 10 degrees," Hale says. The superchilled solution circulates through 11 miles of plastic pipe, cooling the floor to about 15 degrees.
The pipe is not laid in a grid but runs the length of the floor: "If you could look down on it, it'd look like a railroad yard, with a whole ton of parallel tracks," Hale says.
After about 24 hours, when the floor is good and cold, it's sprayed with water, which instantly freezes.
"It becomes like a concrete highway in the wintertime," Hale says.
After a second spraying, which establishes an ice base, the arena crew colors the ice floor white with a mixture of water and paint. If the rink is to be used for ice hockey, the red and blue marker lines are added at this stage.
"It's easier to see the black puck against a white floor," Hale said. "In figure skating, the lighting shows up better on a white background. And," he adds with a touch of sentimentality, "the gray concrete is just not as pretty as white ice."
All sentiment aside, he adds, "And, of course, you wouldn't be able to see our advertisements as well."
After the paint job, the icing process continues. Water is added, layer by layer, until the ice reaches the desired depth. By Thursday of last week, four days into the freezing sequence, the ice was about 1 1/4 inches thick.
This would be adequate for ice hockey, but, surprisingly, not for figure skating. Though it looks punishing, ice hockey is relatively benign to the ice. The players, on rounded skates, do little damage as they sweep across the floor. Because of their speed, their skates throw out a spray of ice crystals, called "snow," but little else. Also, bundled up as they are, the players like a colder temperature, and the colder the ice, the harder the ice.
Figure skaters, by contrast, dig into the ice for their axels and laybacks and come to split-second stops with the aid of toe picks. In their dancer outfits, they also like the ice a little warmer, which equates to softer ice. So, for them, the arena builds the ice floor to a depth of 2 inches, Hale says.
A big, mild man who seems made for the kind of job in which he can come to work in blue jeans and penny loafers, Hale is a hands-on guy.
Originally a high school industrial arts teacher, he became director of parks and recreation for Somerset County, then ran a home repair and construction business before going to work at the arena nine years ago.