Researchers at Purdue University have used Bluetooth signals from mobile phones and other wireless devices to track how long it takes travellers to get through security lines at Indianapolis International airport.
The research could lead to systems that help reduce waits at airport security checkpoints, said Darcy Bullock, a professor of civil engineering at the university.
He said: 'This is the first time anyone has tracked Bluetooth signals to measure how long it takes travellers to get through security lines in the US. We expect the data can be used to help airports make more accurate staffing decisions and aid security officials comparing wait times at airports across the country.'
The wait-time estimation procedure detects and records 'media access control' identification signals, or addresses, each time a Bluetooth device passes a detector.
The researchers used two electronic readers – one at the beginning and one at the end of a security lobby – to record signals from portable devices carried by ticketed passengers.
Robert Spitler, director of security at Indianapolis International airport, said: 'This technique is more efficient than conventional methods and easier to implement because it automatically calculates waiting time.'
The addresses consist of a string of numbers and other characters, but only a portion of each address was recorded to track people, preserving the privacy of travellers.
The data showed security wait times peaked at 20 minutes during the heaviest passenger-processing times in Indianapolis, which occurred around 6am. Wait times diminished rapidly after 6.30am, and levelled off for the rest of the day at about six minutes per passenger.
Bullock said: 'What we are really interested in is what is the worst-case scenario and how long it takes somebody to get through security. What we saw in Indianapolis is that it really never takes anybody longer than 20 minutes. Most of the time, it's less than 10 minutes.'
Researchers used the system from 8 May to 1 June to observe the impact of increased passenger traffic associated with the Indianapolis 500, Bullock said.
The number of passengers passing through Concourse B screening on 18 May was typical at 7,549. However, on 25 May the passengers passing through Concourse B totalled 10,568, an increase of about 40 per cent.
Despite this surge in passengers, the Bluetooth travel-time monitoring showed that screening wait times remained less than 15 minutes throughout the day, Bullock added.
The researchers have used the same technology to measure motor-vehicle travel time, and the Indiana Department of Transportation uses it to monitor traffic on Interstate 65 south of Chicago, where construction frequently causes backups. Motorists are alerted to delays on large electronic signs, providing an opportunity to exit the highway to take alternative routes.
Future work may involve additional airport studies and may be expanded to additional sections of highway, Bullock said.