Loose lithium batteries have been known to cause fires, so on January 1, 2008, the federal government banned the items in checked luggage to reduce the risk of such fires occurring on airplanes. Lithium batteries are, however, allowed in carry-on luggage, and there is no restriction on how many spare lithium batteries you are allowed to carry on-board with you. Lithium batteries typically include batteries found in cell phones, hearing aids and laptop computers.
Explosives are prohibited in both check-in and carry-on baggage. If you accidentally pack an explosive in your check-in luggage, TSA employees may find it by either using an x-ray scan or by physically sifting through the contents of your items. Explosives include dynamite, fireworks, flares of any kind, hand grenades, plastic explosives and blasting caps. Also prohibited in check-in luggage are realistic replicas of plastic explosives, according to the Transportation Security Administration.
Another prohibited item that may be detected in your check-in luggage by either special screening procedures or a physical check are flammables. Flammables can easily start a fire on board an airplane, and are therefore considered dangerous to fly with. The Transportation Security Administration states that flammables include gasoline, gas torches, lighter fluid, flammable paints, and turpentine or paint thinner. Common lighters without lighter fluid are allowed in check-in luggage, but strike-anywhere matches are not permitted.
Certain types of chemicals are prohibited by the Transportation Security Administration in check-in luggage. These chemicals include powdered pool chlorine, liquid bleach, spray paint and tear gas. If you carry a self-defense spray, check and see what percentage of your spray is made from tear gas. The Transportation Security Administration allows self-defense spray to be checked in if the spray contains less than 2% tear gas.
