The question has come up because of Air Canada’s and WestJet’s recent decisions to allow small pets in the cabins of its planes. The CTA is looking into complaints against the two airlines and may end up ordering them to put all animals except service animals back in the cargo bay.

Of course, fur is fur, and service dogs are just as likely to set off an allergic reaction as plain old pet dogs and cats. So, what should be done if an allergy sufferer books the same flight as someone who can’t get around safely without a guide dog?

The Canadian Lung Association suggests the allergy sufferer should have a choice between staying on the flight with the animal or switching to another – at the airline’s expense. There’s no word yet on how the airlines feel about this. Probably they’ll have to accommodate the disabled passengers, even if they lose money by it – and probably they won’t be willing to lose money to accommodate passengers who simply prefer to have their pets with them.

Also, this would give priority to the service dog and its owner. Maybe that’s an unspoken admission that being blind, deaf, or unable to balance is worse than being allergic to animal fur and, therefore, deserves more consideration. Yet, in the United States, a business legally can keep a service animal out if it threatens the health or safety of people or even if it’s disruptive (as when a dog barks during a movie).

It’s going to take time to think this one through.