§ 721.538 Phenol, 4-(1,1-dimethyl- ethyl)-, homopolymer.

(a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phenol, 4-(1,1-dimethylethyl)-, homopolymer (PMN P-95-243; CAS No. 30813-81-1) is subject to reporting under this section for the significant new uses described in paragraph (a)(3) of this section.

(2) High moleculation weight exemption. A batch of the chemical substance may be exempt from the provisions of this rule if the average number molecular weight of the substance is greater than 1,000 and the low molecular weight species below 1,000 and 500 are less than 25 percent and 10 percent, respectively. To be eligible for this exemption, the batch must be individually measured.