46 CFR § 111.106-11
Classification of storage and handling locations of heated combustible liquid cargoes
April 15, 2021
(a) This section applies to locations surrounding the storage and handling of combustible liquid cargoes with closed-cup flashpoints exceeding 60 °C (140 °F).
(b) The interiors of independent storage tanks and integral tanks containing cargoes with closed-cup flashpoints of 60 °C (140 °F) or higher and heated to within 15 °C of their flashpoint are considered Class I Special Division 1 (Zone 0). The hazardous locations in §111.106-9 of this subpart apply.