16 C.F.R. § 1209.32
In addition to the definitions set forth in section 3 of the act and in § 1209.2 of the standard, the following definitions shall apply to this subpart:
Private labeler means an owner of a brand or trademark which is used on the label of cellulose insulation subject to the standard which bears a private label as defined in section 3(a)(7) of the act (15 U.S.C. 2052(a)(7) ) .
Production interval means a time span determined by the manufacturer, private labeler, or importer to be appropriate for conducting a test or series of tests on samples of the cellulose insulation being produced to demonstrate that the product meets the requirements of the standard. An appropriate production interval may vary from test to test. The time period for a production interval shall be short enough to ensure that if the samples selected for testing comply with the standard or a portion of the standard, the insulation produced during the period will meet the standard or the appropriate portion of the standard.
16 C.F.R. §1209.32