Q. Does one have to use Kosher olive oil for Chanukah candles?
A. In principle it is not needed. Yet, Horav Kalman Ochs Shlit’a, mentioned that since it is most common in our days, the adding of products, chemicals and even other oils in small quantities, therefore certified kosher oil should be used. Since it attest that at least the origins of the oil are indeed only pure olive oil without any adulteration,
Rabbi A. Bartfeld as revised by, Horav Dovid Pam, Horav Aharon Miller, Horav Chanoch Ehrentreu and Horav Kalman Ochs Shlit'a