Here's what happens in the kitchen when you tell a restaurant you have an allergy

A waiter's arrestafter a customer suffered a near-fatalallergic reaction from an order mix-up has restaurants wanting to demonstratethey take food allergies seriously.

When a customer with a food allergy walks intoRestaurant Gus, a trendy spot on BeaubienStreetEast in Montreal, the kitchen staff wantsto know two things: the severity of the allergy and whether it's a contact allergy.

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Some food allergies are triggered by eating something in particular, which is generallyeasy enough to accommodate, said the restaurant's owner and chefDavid Ferguson.

But a contact allergy requires added vigilance. These are allergies that can be triggered simply by traces of an allergen.Knivesor cutting boards can transfer traces of certain foods if not washed properly.

"Whenever there is an allergy, we wash everything," Ferguson said. "But if it's contact, we really have to make sureeverything is washed."

'Everything is washed'

The process is straightforward. Soap is applied directly to a knife before it isused to prepare a meal for a client with an allergy. The knifeis scrubbed and then rinsed off.

The same applies toother kitchen implements, especially a cutting board.

"Just last weeksomebody told me, as they were about to eat their tomatosalad, that they were allergic to mangoes," Ferguson said.

"I had already made the tomato salad. I had wiped [the cutting] board, but I hadn't washed it before makingthe tomato salad. So I had to make them a new tomato salad."

Servers atRestaurant Gus are encouraged to always check with the kitchen staff after they are informed of a customer'sallergy.

Recipes can change:Adish that was once safe for an allergic customer may no longer be so after new ingredients are added.

"We always tell our servers ... to come back to the kitchen to make sure," Ferguson. "That's the best way to keep things clean and organized to help people with their allergies.

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