The Transportation Security Administration (TSA) airport screeners have begun taking random chemical swabs from passengers and their bags to check for explosives. 

The metal detectors that are currently used in airports cannot catch materials such as powdered explosives.  The TSA’s new detectors are the size of microwave ovens and easily fit on a push cart and can detect even the smallest amounts of explosives.  These machines are so sensitive that they can sense passengers that have recently taken heart pills that contain nitroglycerin or even those that have recently fired a gun. 

TSA screeners will travel around airports near the gates and checkpoint lines, pushing carts that contain bomb-detection machines.  They will be performing random checks on passengers' hands and carry-on bags, looking for explosive residue.  The screeners will swipe a small swab along a passenger's hand and/or bag, and then run the swab through the reader.  The machines are also being used on checked luggage.

This new program was put into effect in five U.S. airports after the attempted Christmas Day bombing on a U.S.-bound airliner.  The TSA has budgeted $40 million to buy 800 of these new bomb sensors in 2011.  They are hoping that by using this new technology randomly while passengers wait to board their planes, they will cause uncertainty for those who intend to cause harm.  Even the American Civil Liberties Union is supporting this new screening, stating that it is less invasive than the machines that create images of passengers without their clothing.