When customers with allergies dine out, who's responsible for their safety?

Cooking, serving, under arrest? The case of the arrested Quebec waiter has sparked debate about how the restaurant industry grapples with the nearly impossible task of safely feeding customers with allergies.

Toronto's Terroni restaurants have an allergy protocol: when a customer says they have an allergy, the waiter tells a manager, who must approve their order.

When the server gets the OK to enter the order, they must include an allergy alert. This gets printed on a chit and sent to the kitchen in red print rather than black. Managers then check in on the meal while it's being made.

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Customers are supposed to be asked about allergies several times, from when they make a reservation to when they order. A call-out for allergies is printed on the menu.

But even with the best intentions, Terroni owner Cosimo Mammoliti said, mistakes happen.

"If you have a really severe allergy ... we make sure we tell the person [it's] never 100 per cent," he said, noting that food can be cross-contaminated.

Terroni is known for its strict no-substitutions policy. Mammoliti said one of the reasons for the policy is to avoid any food mix-ups that could lead to allergic reactions. If someone is allergic to an ingredient in a dish, the waiter will suggest something else on the menu.

Joint responsibility?

In the Quebec case, some say the waiter is to blame. But Mammoliti said the news of the 22-year-old's arrest came as a shock. He argues the responsibility rests just as much on the customer.

"If I have a personal allergy that is deadly and I'm going out to eat, I am going to be pretty clear explaining how serious my allergy is," said Mammoliti, whose child had an allergy.

"They just have to be very clear, look at the waiter, get his or her attention ... it will stay with the server."

Jen Agg, who runs a handful of restaurants and bars including the Black Hoof in Toronto and Agrikol in Montreal, agrees the customer has a responsibility.

"Servers aren't mind readers," she told CBC News in an email. "But once told, everyone in the kitchen and even the other servers are informed and of course it's written on the ticket. We take it seriously, we want people to have a great experience, not an allergic reaction."

Agg — who has an allergy to cucumbers — said her team looks at how to accommodate dishes for allergic diners on a case-by-case basis, depending on what they ordered.

Jen McDonnell frequently goes out to eat but has a severe allergy to soy products. She puts the responsibility on herself. 

"I'm choosing to eat out," she told CBC News. "I bring my EpiPen and I hope for the best."

McDonnell has had two notable allergic reactions — one at an Asian restaurant, the other at a Toronto street food festival — where her eyes started swelling, her throat closed up and she had to go to the hospital. She had warned the food providers about her allergies.

Now she sticks to restaurants she knows.

"It's restrictive and it's terrible because I love eating out [but] leaving it to a restaurant and leaving it to a waiter is not always possible."

Can't deliver? Don't promise

Laurie Harada takes it a step further. Harada, the executive director of Food Allergy Canada, has a son with severe allergies.

"It all starts with the top," she said, calling out restaurateurs, management and kitchen staff. "It's all about the communication and making sure it's clear and not promising if you can't deliver."

Harada said restaurants must make sure their servers are properly trained to handle customers who have allergies. She said it is not mandatory for restaurants to give all their staff training about allergies — and that it is noticeable when they don't.

That means looking out for waiters who are overconfident in their knowledge of the ingredients of the menu items and don't check with kitchen staff. This has caused Harada problems while dining out with her son.

An estimated 2.5 million Canadians report having a food allergy.

Harada said this means restaurants should make allergies a priority, just like they do for hygiene and making sure that their food is properly handled.

"There's a huge responsibility."