My spouse and I are sharing a kitchen with another adult for the first time in nine years.
New roomie is awesome, and I trust her to the ends of the earth WRT FA stuff. We're keeping the house free of my major allergens--pn, garbanzo, and sunflower--but she asked if I'd be comfortable with tahini in the house, as long as she's very careful about how it's stored / what it comes in contact with. That's theoretically fine by me--sesame is a kind of borderline allergy anyway (I test positive, and because I have other seed allergies and a history of severe adult-onset FA, my allergist said he'd recommend avoiding it in general; but, for instance, I don't worry about shared lines with sesame the way I do with peanuts).
What I'm hoping for help with is coming up with logistical rules--figuring out the maximum intersection of mitigation of risk for me and culinary flexibility for my housemate. To be clear: the call on this is 100% in my court, and I absolutely trust her to stick with whatever guidelines we decide on.
ETA: If it's a factor, it'll really only be the three of us using the kitchen; and we're all a) grown-ups, and b) fairly FA-savvy.