A321
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Time Pressure; Workload
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; Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft
While climbing to our cruise altitude the Captain and I began to hear a noise coming from the cabin that sounded to us like a pressurization leak in the airplane. Shortly thereafter the Captain received a call from the cabin crew; I believe notifying him about the same noise we were hearing. We then asked ATC for a lower altitude in hopes of the noise stopping. Shortly after that the Captain received another call from the cabin crew; when he hung up the phone he told me we were returning to our departure airport ZZZ due to claims of smoke or fumes in the cabin. I then donned my oxygen mask and notified ATC with our intentions to return to ZZZ. We were then given a lower altitude and vectors. We conducted the smoke/fumes checklist. We also decided ZZZ1 airport would be closer and notified ATC we would be landing there. We landed in ZZZ1 without incident where we had the ARFF (airport rescue firefighters) search our aircraft for any hot spots while still on the runway. After no hot spots were found we taxied to the gate where we deplaned normally. The pressurization leak that caused a loud noise and I never heard what the cabin crew smelled in the cabin. I really can't come up with any suggestions that would have prevented this event without knowing what caused the leak and what caused the smell.
A321 First Officer reported a cabin fumes event during climb and cruise level off resulting in a diversion. The fumes were reportedly caused by a pressurization leak.