Four people are hospitalized after carbon monoxide exposure in Drexel Hill DREXEL HILL, Pa. - A scary afternoon for four people in Drexel Hill as they were all exposed to carbon monoxide after a lawn mower was left running inside a garage.Upper Darby police and firefighters were called to the house on the 4200 block of Garrett Road Monday, just after 1 p.m.When they arrived on scene, they found one person unconscious, while three others were suffering from the exposure to the odorless gas.Firefighters took everyone outside and their symptoms dissipated.The four were then transported to a local hospital for observation.