DULUTH - Health, public safety and utility officials inspected a hockey arena Thursday trying to find the source of carbon monoxide that sickened players, coaches and the Zamboni driver Wednesday night.
About 30 people watching or participating in a youth hockey practice were ordered out of Fryberger Arena just after 8 p.m. Wednesday. At least eight people, including players, received oxygen to help treat high levels of carbon monoxide in their blood, though officials Thursday said they understood everyone had recovered.
Gordy Atol, manager of the arena that was built in 1972, said Thursday that air in the building had returned to safe carbon monoxide levels.
It's not yet clear what caused the carbon monoxide levels to increase to dangerous levels. The colorless, odorless gas is produced during combustion of fuels, such as in the propane engine that runs the ice resurfacing vehicle or the arena's gas furnace or gas water heater.
