No one was seriously hurt when an air bag deployed on Dec. 13 as a seat supplier technician was working on a Zodiac Aerospace seat on a plane being readied for delivery, Boeing spokesman Wilson Chow said.

"We understand that employees are concerned," Chow said, adding the company was holding meetings with workers and was implementing additional safeguards and inspections.

"We are confident the system is safe to work on and to be around, and the seat-belt air bag poses no risk to the flying public," Chow said.

The accidental discharge of a seat-belt airbag happened because a bent connector pin caused a short circuit, he said.

Chow confirmed a third incident but could not provide specifics, such as injuries or cause.

A technician for aircraft interior supplier Jamco America died after being struck in the face when a passenger seat air-bag inflator discharged while he and another technician from a different supplier were working on a 777 on Nov. 13, the Seattle Times newspaper reported.

A source who declined to be named said that workers were now following extra safety measures, including using caution tape to cordon off the seats. 

The Dec. 13 incident involved an actual air bag deployment, Chow said, while the Nov. 13 incident happened as the system was partially assembled.

"There is widespread concern," Connie Kelliher, spokeswoman for International Association of Machinists, District Lodge 751, told the newspaper. "We are actively involved and working to ensure our members concerns are addressed."

(Reporting by Alwyn Scott in New York and Eric M. Johnson in Seattle; Editing by Dan Whitcomb in Los Angeles and Jeremy Laurence)