(a) Diesel motor fuel sold at retail shall be identified by the grades of 1-D or 2-D. The grade of diesel motor fuel shall be continuously posted on each face of the dispenser that displays the sale information.

(b) Kerosene sold at retail shall be identified by the grades of 1-K or 2-K.

(2) In the case of 2-K kerosene, an additional statement “WARNING -NOT SUITABLE FOR USE IN UNVENTED HEATERS REQUIRING 1-K KEROSENE” shall be presented in block letters at least one-half inch (½″) in height and one-sixteenth inch (¹/₁₆″) stroke (width of type) on a contrasting background. When kerosene is sold through a retail computing dispenser, the warning statement shall be continuously posted on the upper fifty percent (50 percent) of the dispenser. When kerosene is sold through an approved manually operated stroke pump or using an approved liquid measure, the warning statement shall be conspicuously posted on a sign or placard.