SAN FRANCISCO (CBS/AP) — A fire rig that ran over and killed a 16-year-old Asiana Airlines crash survivor was not equipped with heat-sensing equipment that might have detected her in its path.

Fire officials acknowledged Monday that the older-model engine that ran over Ye Meng Yuan did not have the forward-looking infrared technology.

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The technology measures heat given off by objects on the ground and is now required by the Federal Aviation Administration on all new aircraft rescue trucks.

Other fire rigs at San Francisco International Airport have it, and three more rescue rigs at the airport are in the process of having it installed, Assistant Deputy Fire Chief Dale Carnes said.

He said he did not know if the technology would have prevented Ye’s death.

“That would be complete conjecture,” he said.

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Yuan had survived the crash and was covered in fire retardant foam when the rig hit her while racing to extinguish flames on the plane, authorities have said. They believe she was on the ground when she was struck.

The heat-sensing equipment was developed to detect humans, said Ben Castellano, former acting manager of airport safety for the FAA.

“Had the person been alive — the foam has a cooling action, but the body would still have given off some ambient heat that could have been visible,” he said.

San Mateo County Coroner Robert Foucrault has declined to go into detail on how he determined the teenager was alive before she was struck, but said there was internal hemorrhaging indicating her heart was still beating at the time.

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