Seven people were taken to the hospital after a broken vent pipe on a water heater filled a Valley Stream home with carbon monoxide.

Nassau County police said first responders went to 15 Henrietta St. just before 9 p.m. Sunday for a report of an unresponsive female.

Inside the home, police found two women unresponsive, ages 22 and 47.

Both are still in critical condition, the Valley Stream Fire Department said.

Five more people inside the home, ages 2, 10, 22, 28 and 30, were also exposed to carbon monoxide.

All seven people were taken to Nassau University Medical Center.

Police could not say whether the home had working carbon monoxide alarms, but personal detectors carried by police medics on the scene immediately detected the elevated levels.

Carbon monoxide is a colorless, odorless and tasteless, poisonous gas that reduces the availability of oxygen in the blood and can cause death by asphyxiation.

The incident happened the same day we moved our clocks forward an hour for Daylight Saving Time. This is the time firefighters and other emergency responders generally recommend that you replace the batteries and test all home smoke and carbon monoxide detectors.