Air Canada E190 near Montreal on May 27th 2014, emissions of unknown nature in cabin

An Air Canada Embraer ERJ-190, registration C-FNAX performing flight AC-1177 from Montreal,QC to Calgary,AC (Canada) with 95 people on board, was enroute at FL300 about 120nm northwest of Montreal when the crew declared emergency reporting emissions of unknown nature in the cabin. The aircraft returned to Montreal for a safe landing about 40 minutes later. The aircraft stopped on the runway and was towed to the apron.

The Canadian TSB reported the maintenance team performed an inspection using ultraviolet beams, replaced the filters, cleaned the left hand air conditioning system and performed full power ground runs to purge any odour.