The City of Saint John is monitoring carbon monoxide levels at all of its arenas and may change its safety measures surrounding detection after high levels of the gas made some people sick at the Charles Gorman Arena over the weekend.

Officials say WorkSafeNB is also investigating the high carbon monoxide levels at the arena.

A person had called the arena in Millidgeville on Sunday afternoon, saying he and several teammates who played on Saturday night had experienced flu-like symptoms.

Officials believe elevated carbon monoxide levels at the Charles Gorman Arena stem from a spare ice machine recently put into service. (Google Street View)

Tests then found carbon monoxide levels of more than double the limit for short-term exposure and almost seven times the limit for long-term exposure.

In a statement, the city said an arena attendant used a hand-held device to test the air quality and detected carbon monoxide levels of up to 67 parts per million (ppm).

Health Canada's residential indoor air quality guidelines call for a "short-term limit" of 25 ppm, based on a one-hour average, while the long-term exposure limit is 10 ppm, based on a 24-hour average, according to the website.

Employees also felt effects

Michael Hugenholtz, the deputy commissioner of transportation and environment services, said a further review found that employees also felt the effects of the high carbon monoxide levels.

'Once we did find that levels of carbon monoxide were elevated, we did go back and ask folks who had been on shift … and they did say they had a bit of a headache.' —Michael Hugenholtz, Deputy Commissioner of Transportation & Environment Services

"In hindsight, once we did find that levels of carbon monoxide were elevated, we did go back and ask folks who had been on shift, and been working, and they did say they had a bit of a headache," Hugenholtz said.

"They didn't realize it was caused by carbon monoxide."

"Usually people coming in to use the arena might be there for an hour, a couple hours, and our guys are working a 10-hour shift in the arena," he added.

Hugenholtz said he suspects the elevated levels stem from a spare ice machine that had to be put into service on the weekend.

"We haven't determined that with certainty. We have to look into that a little more," he said.

No regular testing

Hugenholtz said the four rinks operated by the city all have access to a portable air quality detector, but testing isn't done on a regular basis.

"It's not typically used every day and it's not regulated that arenas have carbon monoxide detectors," he said.

"In fact, I think many across the province do not."

Hugenholtz said an investigation underway will determine what kind of counter-measures are required "to make sure this doesn't happen again."

"We really need to understand what the source was, what the root causes are so we can identify appropriate measures," he said.

The building was evacuated Sunday and programming was cancelled while the building was ventilated. Levels are now back to normal.

The natural gas-fired boilers were checked on Monday and no leaks or malfunctions were detected.

When carbon monoxide is inhaled, it reduces the ability of blood to carry oxygen, according to the Health Canada website.

Low levels can cause symptoms such as headaches, tiredness, shortness of breath and impaired motor functions.

High levels over a long period of time can cause dizziness, chest pain, tiredness, poor vision and difficulty thinking.

Exposure to very high levels can cause convulsions, coma and even death, the website states.

It is a common byproduct of the burning of propane, natural gas, gasoline, oil, coal and wood.