Replacing gas-powered vehicles with electric vehicles is key to combating climate change. But Health Canada is also touting the ability of one particular electric vehicle to curb indoor air pollution in places where children and adults play and exercise: electric ice machines.
In Canada, most arena ice machines, such as Zambonis, run on natural gas or propane.
Burning these fuels can produce air pollutants such as carbon monoxide and nitrogen oxides – the same ones produced by gas stoves, raising concerns about air pollution in people’s homes.
Health effects of air pollution in the arena
At indoor arenas, cases have made the news of ice rinks having to close, and sometimes dozens of people have been hospitalized for high levels of carbon monoxide, which can lead to acute poisoning and be fatal.
There have also been clusters of nitric oxide-related illnesses caused by pollution, including one in British Columbia in 2019. Nitrogen oxides can cause respiratory irritation and breathing difficulties, but the effects aren’t always immediate and can take a day or two to spread delay.
Nitrogen oxides are also known to trigger asthma, which is common in ice hockey players. Researchers suspect this is compounded by a combination of cold air and indoor air pollutants during intense exercise.
Traditionally, arena-related disease outbreaks are attributed to a combination of faulty ice machines and inadequate ventilation in many older facilities. To make matters worse, cold air sinks, so even with ventilation, polluted air tends to remain near the ice surface – a problem highlighted by arena-related COVID-19 outbreaks.
Aaron Wilson, a scientific reviewer in Health Canada’s Indoor Air Pollutant Assessment Division, said he noticed a few years ago that local officials often asked for advice on how best to prevent air quality problems in local arenas and can fix it.
“We quickly realized that there wasn’t a lot of information,” he said. There was not even data on what typical levels of pollution existed in ice rinks and how much ventilation was required.
What researchers have learned about air quality in arenas
From 2017 to 2020, Health Canada, along with the Saskatchewan Health Department, conducted a study to find out. They monitored carbon monoxide and nitrogen oxides in 16 arenas in Ottawa and northeast Saskatchewan.
The good news? Carbon monoxide levels were generally within Health Canada guidelines.
However, in seven of 16 monitored arenas, nitrogen oxides exceeded Health Canada’s short-term exposure limit at least at times.
These pollutants accumulated throughout the day as the ice reappeared, and peaked in the evening. And they were never completely cleared out by the ventilation system overnight. Wilson said that early in the day, nitric oxide levels could be up to four times what they were outside – “before they even do an arena refurbishment.”
Ventilation vs. electric ice resurfacing equipment
Researchers tried different strategies to clean up the pollution.
Wilson said the ventilation was effective in certain types of arenas but not in others. Additional ventilation also made the building sometimes convenient for people in the arena, such as spectators, uncomfortably cold and could drive up heating bills.
However, one solution was extremely effective: Replacing gas-powered ice resurfacing machines with electric ones more or less eliminated indoor air pollution, Health Canada found.
Even at an ice rink, where nitric oxide levels were several times above health guidelines, this solution brought them to or below levels outdoors, Wilson said.
In 2021, Health Canada issued guidelines to improve arena air quality based on the study. Using electric ice straighteners and edgers to tend the ice to eliminate the main sources of contaminants was his top recommendation.
“In the long term, I think this is the solution to ice rink air pollution,” Wilson said.
Climate change is motivating the electric switch
Electric ice resurfacing machines have actually been around for decades – Zamboni debuted its first model at the 1960 Winter Olympics in Squaw Valley, California, but didn’t start selling a commercial battery-powered model until 1978.
Several brands of electric ice resurfacing machines are available in Canada today, as well as electric edgers for smoothing the sides of the ice rink.
Steve Kovacevic is the general manager of Resurfice, based in Elmira, Ontario, which offers both lead-acid and lithium-ion electric models.
While fossil fuel options, which are still cheaper, used to be more popular, he said he’s noticed that now when municipalities are issuing bids for new ice resurfacing machines, “they’re trying to switch to electric machines — there’s no doubt about that.” “
The Zamboni brand alone has over 400 electric machines across the country, according to Greg Dean, the company’s vice president of sales and brand management. The largest fleet to date is in Montreal with 31, followed by Strathcona County, Alta. with 13 and London, Ontario with 12.
“There has been a huge increase in interest in electronics,” he said in an email.
Some provinces like Alberta and BC are offering climate finance to offset the higher initial cost of electric machines and it seems to have made a difference.
Terry Piche, director of training, research and development at the Ontario Recreation Facilities Association, said his province has also seen a shift toward electrical appliances over the past 15 years. Now he estimates that a quarter of Ontario’s roughly 1,000 ice rinks are serviced by electric ice resurfacing machines – and the number is growing every year.
While electric models are more expensive than fossil-fuel versions (about $50,000 more per machine), his group estimates that arenas will break even after eight years due to lower fuel and maintenance costs.
Does it make a difference to users?
Climate change is the top reason communities cite for switching, and the health co-benefits are not usually a priority – although some communities mention safety benefits and reduced stress on ventilation systems.
Mississauga, Ontario is one city that is in the process of replacing all 22 ice resurfacing machines with electric ones.
Shari Lichterman, Mississauga’s acting city manager, said this is part of the municipality’s climate protection plan, which calls for the electrification of the entire city fleet from buses to mowers.
Lichterman, who is also chair of Parks and Recreation Ontario, said air quality has not been a major issue in her city’s arenas due to monitoring and ventilation systems, although it may be the case in arenas in other communities.
“But as far as we can allay those concerns at all,” she said, “of course we want to do that.”
Still, clean air in the arena is something that users notice and appreciate. On a weekday afternoon, a group of players from the Mississauga Chargers junior hockey team practiced at the city’s Port Credit Memorial Arena on ice re-smoothed by the rink’s electric Zamboni.
Head coach Joe Washkurak said that decades ago in the old arenas where he first started playing hockey, “you could always smell the propane from the old Zambonis, and that wasn’t a very good hockey smell.” He also recalls from gas leaks postponed games.
Nowadays the atmosphere in the arena is more pleasant for practicing. “No pun intended, but it’s a breath of fresh air.”
