40 CFR §766.25

1. (a)Listing of chemical substances. Chemical substances required to be tested for HDDs/HDFs under this rule are listed in this section. The listing is by Chemical Abstracts Service (CAS) Number and common name.
   1. (1)Chemicals substances known to be manufactured between January 1, 1984 and date of promulgation of this part.
   2. (2)Chemicals not known to be manufactured between January 1, 1984 and the date of promulgation of this part.
2. (b)Grade to be tested. If the same process is used to manufacture all grades of the same chemical substance, only one grade need be tested. The grade to be tested must be the grade subject to the most intense heat and alkalinity for the longest duration of time, manufactured under each different process. If the heat, alkalinity and duration of reaction do not differ for various grades, the test substance must be the grade of chemical substance with the highest volume of sales.