California Code, Public Resources Code - PRC § 42775

(a) For the purposes of implementing and enforcing this chapter, the board shall set newsprint comparable quality standards for each of the grades of newsprint specified in Section 42753 to determine the comparable quality of recycled-content newsprint to virgin material. These standards shall be based on the average numerical standards of printing opacity, brightness level, and cross machine tear strength available from all producers selling recycled-content newsprint in the state in quantities of at least 5,000 metric tons per year. The board shall set standards which deviate from this average by not more than 5 percent.

(b) The board shall review its standards at least once every two years and determine whether they should be adjusted to reflect changes in industry standards and practices, and, if so, the board shall set new standards according to the criteria in subdivision (a).