“Firefighters discovered dangerous levels of carbon monoxide at the Icenter Friday afternoon while responding to an unrelated medical call… portable carbon monoxide detectors attached to firefighters’ gear alerted them of the issue when they walked into the building… Salem’s building inspector will follow up Monday to find out why detectors installed at the Icenter were not sounding when first responders arrived”

Firefighters discover carbon monoxide in Icenter during separate response | New Hampshire | eagletribune.com