US VISIT began collecting the two index fingerprints of visitors to the U.S. in 2004. Ten prints give the U.S. Department of Homeland Security more information to work with and the ability to check other government databases.

Now when the visitors are scanned at the airport their information is checked against a watch list of 3.2 million prints. Eventually the US-VISIT database will be able to query the FBI’s IAFIS fingerprint database, which holds approximately 55 million sets of prints, in real time as well. Currently that search is done at a later time.

O’Hare is the latest airport to make the switch to 10 prints following Boston’s Logan Airport last week, Hartsfield Jackson Atlanta International Airport earlier in the month and Washington Dulles International Airport in November.

US VISIT officials are analyzing data from those sites and seeing how taking the additional prints impacts the time at the checkpoints. At O’Hare on Tuesday, ThirdFactor.com witnessed four passengers from Tokyo going though the new procedures. It took less than two minutes for all passengers to get through the entire check in process with the longest taking approximately one minute 44 seconds and shortest taking one minute, 12 seconds.

O’Hare Customs and Border Protection officials are using the L-Scan Guardian fingerprint scanners from Cross Match Technologies, Palm Beach Gardens, Fla. The Identix Touch Print 4100 Enhances Definition Device is also being used at some airports.