The worker killed yesterday at Denver International Airport is a 46-year-old Pennsylvania family man with a son serving in the Army in Iraq.

In a freak, predawn accident, Robert L. Genzler, 46, of Beaver Falls, Pa., was hit by a giant sweeping machine as workers scrubbed tire rubber from a DIA runway.

Genzler worked for Rampart Hydro Services, a Pennyslvania firm that uses trucks blasting high-pressure water to strip rubber residue left by landing jetliners from runways.

Denver police said the DIA worker driving the sweeper lost sight of Genzler, apparently because the man had bent over to pick up an object on the runway that was closed for cleaning, police said.

Genzler is survived by his wife, Barbara, and their three children, Sean, Andrew and Lisa, Rampart officials said in a statement today. Genzler's son, Sean, who is married with his own young son, is serving in Iraq.

Federal and local authorities said an investigation into the death will probably take two months to complete. It will look into the mechanics of the scrubbing machine and why Genzler — who had been driving a vehicle — was on foot when struck at runway 16L-34R.

"We're doing a thorough job, so that it doesn't occur again in the future," said Herb Gibson, Denver area director for Occupational Safety and Health Administration.

Genzler's identity was confirmed by fingerprints during an autopsy today by the Denver medical examiner's office.

The runway was closed for about seven hours after the accident, but air traffic was not affected, said DIA spokesman Chuck Cannon.

The last worker death at DIA occurred in January 2005 when a United Airlines employee died after a jet extinguisher exploded in a hangar, Gibson said.

Monday's death comes less than a week after an electrician drove on a DIA runway without authorization.

DIA restricted motor vehicle access to the airfield and increased driver training after that violation. No aircraft were in the area where the motorist crossed the runway, officials said.

gathrighta@RockyMountainNews.com or 303-954-5486.