Event Summary
Moderate turbulence was encountered as the airplane climbed through flight level 180 while in clouds. Prior to the event, there were no weather returns indicating turbulence, nor were there any reports of turbulence from Air Traffic Control or other aircraft in the area.
Injuries
During the turbulence, one flight attendant who was in the aft galley received minor injuries. Additionally, a passenger sustained a broken rib when the male portion of her seat belt disconnected from its attach point, causing her to be thrown from her seat into the aisle.
Seat Belt Incident
The attach point and the latching mechanism of the seat belt were both found to be intact. The disconnection occurred at the point where the male portion of the belt separates from the attach point, despite the hardware being undamaged.