Postal workers on the picket lines in Calgary

Don't bother checking your mailbox in Calgary on Thursday.

Postal workers have walked off the job as part of a rotating strike action across the country.

The Canadian Union of Postal Workers began strike action in Calgary on Wednesday evening, which is expected to last until 6 p.m. Thursday.

Anna Beale is a postal clerk with Canada Post and an executive with the local postal workers' union.

She says postal workers are fighting for improved job security, an end to forced overtime and better health and safety measures.

• Canada Post rotating strike hits Calgary

"We've had enough. We've been trying to get them to negotiate for 10 months and here we stand," she said.

"We don't want to be out here. We'd rather be inside working, getting the public their mail. This is our way of saying, 'Canada Post, OK, enough. This is enough. Get seriously negotiating."

The union represents more than 54,000 workers Canada-wide in the postal, delivery, logistics, transportation and communication sectors.

Beale says one concern workers have centres around parcel deliveries.

"Canada Post last year bragged, rightly so, that they were the No. 1 parcel delivery company in Canada, delivered the most parcels, and we were proud of that," she said.

"But they didn't change the letter carrier walks to account for all the extra volume that letter carriers have to deliver in those parcels. And as a result, carriers are having to worked forced overtime, [working] 12 hours a day ... and that's no good. We don't get any kind of family life. Our injury rate has soared."

Committed to bargaining process

In a release, Canada Post says it continues to operate across the rest of Canada and is accepting and delivering mail and parcels in all other locations.

It adds Canada Post remains "committed to the bargaining process."

"The corporation has made significant offers to CUPW which include increased wages, job securityand improved benefits and has not asked for any concessions in return," it reads.

Kevin Gillis, a letter carrier for 14 years, says Canada Post's offer of a 1.5 per cent wage increase over a four-year contract was "embarrassing."

"We all want to do our job, we don't want to inflame the public, it's not their fault their government is unreasonable," he said. "You won't get your weed today but chill out, you'll get it tomorrow."

Rotating strikes began on Monday, after negotiators failed to reach a new contract agreement before the union's strike deadline.

Canada Post is warning customers to expect delivery delays.

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