‘TORONTO – Porter Airlines’ customer service agents in Toronto have unionized, becoming the largest group of employees to organize at the privately owned regional airline.

The Canada Industrial Relations Board says it has approved Unifor as the bargaining agent for the employees.

The decision affects 109 airport agents, excluding co-op students, that work at Billy Bishop Toronto City Airport.

The group joins 77 ramp personnel and baggage handlers who joined Unifor this fall.

Refuellers represented by the Canadian Office and Professional Employees union ended a more than five-month strike in June 2013 after reaching its first collective agreement with Porter FBO, a subsidiary of Porter Aviation Holdings Inc., which operates the airline. The National Organized Workers union represents airport cleaning staff.

Unifor organizing director John Aman said the union has begun to prepare for negotiations aimed at reaching a first collective agreement.

Porter has about 1,400 employees.