(a) Except as specified in subdivision (b) of this section, before service or sale in ready-to-eat form, raw, raw-marinated, partially cooked or marinated-partially cooked fish other than molluscan shellfish shall be frozen throughout to a temperature of:

(b) If the fish are tuna of the species Thunnus alalunga, Thunnus albacares (Yellowfin tuna), Thunnus atlanticus, Thunnus maccoyii (Bluefin tuna, Southern), Thunnus obesus (Bigeye tuna), and Thunnus thynnus (Bluefin tuna, Northern), or if they are species of fish recognized as not being susceptible to parasites of concern; the fish may be served or sold in a raw, raw-marinated, or partially cooked ready-to-eat form without freezing as specified under subdivision (a) of this section.

(c) Except as specified in subdivisions (b) and (d) of this section, if raw, raw-marinated, partially cooked, or marinated-partially cooked fish are served or sold in ready-to-eat form, the person in charge shall record the freezing temperature and time to which the fish are subjected and shall retain the records at the food establishment for at least 90 calendar days beyond the time of service or sale of the fish.

(d) If the fish are frozen by a supplier, a written agreement or statement from the supplier stipulating that the fish supplied are frozen to a temperature and for a time specified under subdivision (a) of this section may substitute for the records specified under subdivision (c) of this section.