OAK BROOK (STMW) — Carbon monoxide detectors were not working in a west suburban Oak Brook mansion where an 86-year-old man died and seven women were injured as a result of a leak Thursday morning.

The Oak Brook Fire Department was called to a home at 2900 Oak Brook Hills Road about 9:45 a.m. for a female having difficulty breathing, Pioneer Press reports.

Firefighters found high levels of carbon monoxide upon arrival, and measured 1,000 parts per million, said Acting Fire Chief Gary Clark, who said symptoms of carbon monoxide poisoning begin to appear at 200 parts per million.

“Even at 1,000 (parts per million) it could have been fatal to all of them,” Clark said.

Pei Tang Yeh, 86, was found unresponsive in a bathroom of the home, where he also lived, authorities said. There were eight other people in the home, ages 20 to 70, including family and some domestic help.

Seven other people were reported hospitalized, according to a statement issued by Oak Brook police.

Clark said the carbon monoxide readings were strongest near an indoor pool of the approximately 15,000-square-foot house.

A water heater was determined to be the proximate cause of the leak, police said.

The house was equipped with carbon monoxide detectors, but they were not working at the time of the leak, according to police.

Ambulances from five departments responded to the home and helped transport victims to Good Samaritan Hospital in Downers Grove. Clark said no foul play is suspected in the incident.

The investigation was reviewed with the DuPage County State’s Attorney’s office, and no criminal charges will be filed in connection with the leak, police said.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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