Roughly 700 ground crew workers at Toronto's Pearson airport walked off the job Thursday night after voting to strike during the busy travel season of summer holidays.

The members of Teamsters Local 419 began picketing around 10 p.m. ET, after learning that 95 per cent of those who voted had rejected the offer from Swissport. 

The company services 30 airlines at the airport including Sunwing, Air Transat, Air France and British Airways.

Earlier Thursday, the Greater Toronto Airports Authority said it had a contingency plan in the event of a strike or labour disruption, but did not provide details.

Instead, it suggested passengers check in with the various airlines to see if the strike would delay their travel plans.

The striking workers include baggage and cargo handlers, cabin cleaners and other ground staff, as well as some employees who tow planes as part of the airlines' Swissport services.

The overwhelming strike result came as little surprise as the union's bargaining team had appealed to its members to reject the proposed contract. The union has said it's struggled to find common ground on changes Swissport wants to make to scheduling.

Picketers have no plans to delay travellers or any aircraft, the local's vice president said Thursday, saying that he and his colleagues just want a fair deal so they can get back to work.  

"The fight is not with the general public it's with Swissport management," Harjinder Badial told CBC Toronto. "We're not here to delay any sort of flights or anything like that. We sent a message to Swissport tonight and I hope they're listening."

Teamsters baggage strike Toronto airport

Teamsters Local 419 vice president Harjinder Badial alleges that temporary workers Swissport has hired have been involved in numerous accidents. The union has filed a complaint with the Canadian Industrial Relations Board. (Gary Asselstine/CBC)

The union had already set up picket lines around Terminal 3 and a cargo terminal near Swissport's administrative offices.

Badial said that there have already been delays, but blamed those on the 250 contract workers hired by Swissport in May.

"I know there has been a few delays today, with these temporary agency workers," he said. "There's been a lot of incidents as well, and at the end of the day there certainly will be an impact and we will try to minimize it as much as possible."

Airlines say they've made plans to curb delays

Air Transat said it was taking measures to ensure none of its flights would be delayed if a strike occurs. British Airways said it had a contingency plan and would continue to operate all its flights.

WestJet, which does not work with Swissport, said it was aware of the situation and advised passengers to arrive early for their flights to avoid delays. Air Canada said there will be no impact to its customers as it operates its own baggage handling at Pearson.

Pierre Payette, Swissport Canada's vice-president of operations, said the company has bargained in good faith throughout contract talks. It also put out a memo to employees Tuesday, asking them to vote in favour of the company's final offer.

Swissport hired 250 contract workers

The union, however, has described Swissport's contract as unfair to its workers. It has also taken issue with the company's decision to hire 250 temporary workers last May.

The union filed a complaint with the Canadian Industrial Relations Board over that matter, alleging the temporary workers are poorly trained and have been involved in multiple accidents over the past few months.

Swissport said it "categorically denies" those allegations.

With files from The Canadian Press