Delta Air Lines is testing whether facial recognition technology can speed the bag-checking process.

It has installed four self-service bag drop machines at Minneapolis-St. Paul International Airport, one of which will be equipped with the technology to match customers with their passport photos.

That eliminates the need for a Delta agent to verify a passenger’s identity.

Delta said that automated capability is a first for a U.S. airline.

The kiosks will be available to both domestic and international passengers, but to use the specially equipped machine, a passenger must be carrying a U.S. passport.

Passengers using other forms of identification can use one of the three other kiosks, which enable self-bag-tagging.

Delta will collect customer feedback during the trial and run process analyses to ensure that the new system improves the overall customer experience.

The carrier also will be looking to confirm studies that have shown that self-service bag drops can process twice as many customers per hour. It has invested $600,000 in the four machines.

Delta has introduced a number of initiatives to streamline airport processes in recent years.

Among them is the use of radio frequency identification technology to track bags. The technology enables passengers to determine the precise location of their bags by checking the Fly Delta Mobile app or the carrier’s website.

It also added interactive airport wayfinding maps on the app.

The carrier’s ultimate goal is to reduce congestion in airport lobbies, taking some of the tension out of checking in.

Finnair is testing facial recognition for check-in. KLM is testing it to speed up the boarding process.