Carbon monoxide sends 5 to hospital on Wednesday morning

Five people were rushed to hospital in Calgary with carbon monoxide poisoning on Wednesday morning.

The incident took place at a building under constructionin the 600 block of SeventhAvenue S.E.

Calgary firefighters saythey responded just after 7 a.m. andfound an unconscious man inside the worksite office, which was located in a parkade.

"Reports indicate that the worker may have been in the office for approximately an hour," reads a news release.

A Calgary Fire Department spokesperson says it's believed a heater inside the office gave off the carbon monoxide, although that has yet to be confirmed. The area where the unconscious man was found had readings as high as400 parts per million.

All workers were evacuated from the site and five of them were taken to hospital. All were in non-life-threatening condition.

Twenty-five people in total were on the job site that was evacuated.

Occupational Health and Safetyis investigating.

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