According to a Wednesday statement by the Transportation Security Administration (TSA), the failed al-Qaida attack, on the Amsterdam-Detroit Northwest Flight on Christmas Day, has prompted the airport security screeners to expand the use of swabs, which can detect explosives’ residues, to the hands of passengers and their carry-on baggage.

Thus far, the airport security screeners have run a swab – which is put into a machine that hunts for molecules of explosives-like substances - chiefly over the carry-on items of the passengers, with focus largely being on the baggage handles or zippers or other such likely-to-have-touched spots. However, the use of the swabs will now be extended to the passengers’ hands as well.

Noting that random swabbing of US air travelers’ hands and carry-on items will commence henceforth, the TSA elaborated: “This additional screening measure could take place at the security checkpoint, in the checkpoint queue, or boarding areas.”

With TSA’s random swabbing move taking effect, the agency’s spokeswoman Kristin Lee said that passengers will soon notice the expanded random checks at 450 countrywide airports, to be phased during the coming weeks.

The agency has specified that the expanded use of swabs is part of its “layered approach” to aviation security. It also said that the screening being a random one, passengers might not see “the same thing at every airport or each time they travel.”