Careless or sloppy recycling can be dangerous for the workers at Calgary's recycling plant, the city says, asking for a reduction in "wish-cycling."

"It is people's lives you are putting at risk," Sharon Howland told the Calgary Eyeopener on Monday.

Howland is the recycling and waste management project lead and she pulled back the curtains of the Cascades Recovery+ facility in southeast Calgary.

"That's an empty or expired bear spray canister, those little green camping propane tanks, scrap metal, garden hoses. You put those things in your blue cart and they can cause fire in the collection truck or damage to facility equipment," she said.

Sharon Howland is the recycling and waste management project lead. She pulled back the curtains of the Cascades Recovery+ facility for the Calgary Eyeopener radio show on Monday. (Monty Kruger/CBC)

"Last week, we had another evacuation because an empty bear spray canister got crushed on the floor by a loader, went through the sorting equipment and then everyone in the building is exposed to residual bear spray. There is always something left in those canisters."

The facility, about 100,000 square feet in size, manages between 100 and 200 tonnes of recycling every two to three days, running continuously six days a week.

The blue carts are not for electronics, old electrical cords, or things like bear spray, which can cause huge problems and challenges. (Angela Knight/CBC)

"People are always very curious about where their recycling goes once it's been collected from their blue carts," Howland said.

And generally, they want to do the right thing.

"About 95 per cent of Calgarians set their blue cart out on a regular basis."

But knowledge can make a big difference.

"We are seeing too much of that wish-cycling behaviour where you are putting something in, hoping, wishing, dreaming that it is recyclable, but you haven't checked to see if it is," Howland said.

LISTEN to the full interview, starts at 16:00

Broadly, the wish-cycling mistakes fall into two categories: packing and safety.

"There may be a piece of packaging, maybe a plastic pouch. It looks similar to what you have recycled in the past but it's actually not compatible with the sorting system," Howland explained.

The blue carts are not for electronics, old electrical cords, of things like bear spray, which can cause huge problems and challenges.

"There are lots of moving parts in this facility," she said.

Careless or sloppy recycling can be dangerous for the workers at Calgary’s recycling plant, the city says. (Angela Knight/CBC)

"Wired headphones, extension cords, garden hoses, can get wrapped up around that equipment and cause hours of shutdown. We don't have time or space for hours of shutdown around here. There is so much recycling coming in the front door, we need to keep equipment and people moving continuously."

The city offers online resources to help make sense of recycling choices including specific search tools.

And if you still have questions, Howland is part of a panel discussion called Let's talk about waste at the Calgary Central Library on Tuesday starting at 6 p.m., but you'll need tickets.