Kenosha, WI –

“A mechanical problem caused carbon monoxide levels to spike at Hob Nob restaurant…the Somers Fire Department was called to the restaurant…for 12 people – a mix of restaurant staff and customers – complaining they were feeling ill. ‘We found carbon monoxide levels at 600 parts per million…'”

https://www.kenoshanews.com/news/local/article_8bd58c8b-bf2d-546d-bef6-659526694731.html