The state of Massachusetts has found a solution to the arena air quality problem uncovered in a CBC investigation earlier this week: electric ice resurfacing machines.
 
The CBC found many arenas across Canada had high levels of ultrafine particulate pollution, primarily created by propane- or natural-gas-powered ice-resurfacing machines.

Todd LaFleur, program manager for conservation and recreation with the state of Massachusetts, said air quality was a problem in enclosed rinks there about a decade ago.

The arenas switched to electric, battery-powered ice resurfacers, and LaFleur said there's been a "huge" improvement in air quality.

"With the propane machines, we required that our rink operators had the doors open on both sides, and plus they had to have all the ventilating equipment running," he told CBC News on Wednesday.

"Now they don't have to do that — which of course is a savings for the rink itself when it comes to energy costs  — [and] you don't have any of the internal poor air."

Air drier, ice harder

LaFleur acknowledged that the electric machines are heavier and more expensive; the machine costs around $100,000, and a battery pack costs $5,000 to $6,000, he said.

But he said the they do an excellent job and keep the air drier than propane- or gas-powered machines, which helps the ice to remain hard, which pleases hockey players.

City officials in Winnipeg, one of five cities where CBC tested arenas' air quality, said they would consult with health experts before deciding if they would retest the arenas or take any other action.

There are no health standards for ultrafine particulate pollution, but studies have linked exposure to high levels of ultrafine particulate matter with decrease in lung function.

Almost one-quarter of the arenas that were part of the investigation had test results that showed more than 60,000 particles of pollution per cubic centimetre, a level that an expert consulted by CBC said is cause for concern.

At Winnipeg's West Kildonan Arena, which like most of the Winnipeg arenas tested uses a propane ice resurfacer, the maximum count during CBC's spot check was 250,000 particles — the highest of any arena tested and more than double the amount expected near a busy freeway.

Four of the arenas tested in CBC's investigation use electric ice resurfacers.  Maximum particulate counts during CBC spot checks at those arenas averaged 14,400 particles per cubic centimetre, a rating slightly higher than that expected in a typical indoor office environment.