Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Time Pressure; Troubleshooting; Physiological - Other
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Diverted; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification
Aircraft
At FL340; noticed the smell of fuel in the cockpit. Complied with QRH procedures. [Advised ATC] and landed at ZZZ without incident. Fuel Fumes from unknown origin. Fix the aircraft.
At cruise alt 34;000 feet; we noticed a smell of jet fuel in the flight deck. It was intermittent at first on the First Officer side and then suddenly got stronger throughout the flight deck. We donned the O2 masks and complied with QRH checklists. Diverted to ZZZ. ATC was advised. No odor was smelled in the cabin at first; but half way through the descent; the flight attendants started smelling a fuel odor in the aft cabin and galley. Upon landing at ZZZ [Runway] XXL; we stopped on the runway and had the aircraft checked for a fuel leak prior to taxiing to the gate. As the aircraft was being checked out; the aft flight attendants reported the odor/fumes increasing in intensity. When asked if they believed an evacuation was necessary; they said no. We eventually taxied to the gate and deplaned all passengers to avoid any unnecessary additional exposure to possible fumes. Multiple announcements to passengers were made throughout the event by the cockpit and cabin crew. After all passengers were deplaned the flight deck and cabin crew jointly debriefed at an empty gate. It was determined that nobody needed medical attention. Fumes event; cause unknown. [No suggestions; as it was an issue with the aircraft. Other suggestion is that it did not occur to the flight attendants to don their PBEs although they were exposed to potentially toxic fumes. I also did not - until after the incident - think of reminding them. Should be stressed more in training that flight attendants also need to protect themselves with PBEs during fume events not just smoke events.
Air carrier flight crew reported at cruise the flight deck and passenger cabin began to smell of fuel. The crew completed the QRH and diverted.