(a) Production volume will be measured over a period that begins one calendar year before publication of the final test rule in the Federal Register and continues up to the latest data available upon resolution of a dispute.

(b) For the purpose of determining fair reimbursement shares, production volume shall include amounts of the test chemical imported in bulk form and mixtures, and the total domestic production of the chemical including that produced as a byproduct. Impurities will not be included unless the test rule specifically includes them.

(c) Amounts of the test chemical manufactured for export will not be included unless covered by a finding under TSCA section 12(a)(2).

(d) Chemicals excluded from the jurisdiction of TSCA by section 3(2)(B) need not be included in the computation of production volume. (Chemicals used as intermediates to produce pesticides are covered by TSCA.)

(e) The burden of establishing the fact that particular amounts of the test chemical are produced for exempt purposes lies with the party seeking to exclude those amounts from the calculation of his production volume.