KRIENS: Family of four almost suffocated in the Sonnenberg tunnel After Saturday shopping, a family of four is driving on the A2 motorway when carbon dioxide suddenly fills the interior of the car. Thanks to an attentive motorist, they survived.​
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The incident occurred at noon on Saturday, at 11.45 a.m., on the A2 motorway in Kriens. A family of four was on their way home after shopping. Shortly before the Sonnenberg tunnel entrance, the CO2 gas cylinder for the aquarium leaked after a defect, according to the Lucerne police.​
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The gas quickly poured out and filled the interior of the vehicle. In the middle of the tunnel, the car slowed down more and more, came to a standstill and then rolled backwards into the fast lane. For several minutes, following road users drove past the family until finally someone stopped and inquired about the occupants.​
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The entire family sat unconscious in the car. After the doors were opened, they gradually recovered. Two ambulances took the family to the hospital. They were unharmed. However, the family was very lucky in misfortune: According to forensic medicine, there was an extremely high risk of suffocation for the unconscious.​