Jason Hegg's 22-month-old son Carter has asthma, and because of his age, Carter can't use an inhaler. Instead, his family carries a portable nebulizer, a device that allows Carter to breathe a medicated mist, with them when they travel. Or at any rate, they try to. According to Hegg, federal Transportation Security Administration screeners at Duluth International Airport refused to allow him to board a plane with the nebulizer, even after he showed them information from a TSA Web site saying nebulizers are permitted on planes. Hegg says he can produce witnesses who say the TSA officials at Duluth asked each other why he had to bring the nebulizer on board, since "there's oxygen on the plane."