Are sushi restaurants safe?

Even though we've eaten at sushi restaurants several times with DJ in tow, that was before his peanut allergy diagnosis. I'm heading out at lunch to Bikkuri to grab a dynamite roll so will be sure to ask if any peanuts or nuts are present in Japanese fare. While I doubt DJ will like sushi - at least yet - perhaps the teriyaki offerings will be safe, providing with us another alternative for eating out in a peanut/nut free environment with our PA tyke.