METHUEN (CBS) – A Methuen family feels lucky to be alive after a carbon monoxide leak sent four of them to the hospital.

The leak was caused by a generator outside the home that was only a few inches from the family’s garage door. Fumes somehow seeped inside.

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Though the home had carbon monoxide detectors, they were hard-wired. So without power, the detectors did not work.

The Laurent family — now back home after being treated at a local hospital — was using a generator after Sunday’s storm knocked out the power, officials said.

This home on West Street in Methuen was vented after the CO leak early Thursday. (Photo credit: David Robichaud – WBZ-TV)

Firefighters were called to the house on West Street around 3 a.m. and found CO levels at 500 parts per million. Evacuations are necessary if levels are over nine parts per million, said Methuen Fire Chief Tim Sheehy.

“Anything over nine, you should be getting out… If you’re exposed to over 800, I think it’s a 2- to 3-hour window for survival,” Sheehy said.

Michel Laurent lives at the home. She said both her children were nauseous, vomiting, and had headaches. She and her mother experience dizziness and nausea.

When Michel went to wake up her son, he didn’t respond. So she physically removed him from the bed and the family got out of the house.

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“We were at deadly levels. I’m shocked. I’m a nurse, so I know this. I’m shocked to be alive,” said Michel Laurent.

Michel Laurent shows the generator that nearly killed her family. (WBZ-TV)

Authorities were able to safely vent the house.

Sheehy said the West Street case was the third generator-related issue they’ve responded to. Ideally, residents should safely keep generators some 50 feet away from their home, he said.

About 2,500 homes and businesses in Methuen were still without power as of 9 a.m. Thursday because of the storm Sunday night.

When the Laurent family returned from the hospital, there was a National Grid crew restoring power, something Michel said lightheartedly she didn’t think was a coincidence.

“I was coming in and I said ‘My neighbors better thank me for this one,’” she joked.

WBZ NewsRadio 1030’s Ben Parker reports

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