Section 1632.7 - Tape edge substitution procedure(a) Sections 1632.1(j) and (k) provide in part that "a change in existing material shall be deemed a difference in materials for purposes of prototype definition unless it is shown to the satisfaction of the Consumer Product Safety Commission that such change will not reduce the ignition resistance" of the mattress prototype or the mattress pad prototype.(b) The Commission will regard a showing "to the satisfaction of the Consumer Product Safety Commission" to have been made with respect to materials substitution of items such as flange materials and tapes at the tape edge under the following circumstances:(1) The mattress or mattress pad prototype has been qualified previously under the provisions of § 1632.3 ; and(2) A substitution of materials involving only tape edge construction is contemplated; and(3) A prototype mattress or mattress pad incorporating the substitute materials has been tested in accordance with applicable procedures in § 1632.4 by placing 36 cigarettes (18 per surface-9 bare and 9 two-sheet) at tape edge locations with no test failure as determined by applying the test criterion of § 1632.3(b) ; and(4) Records are maintained setting forth the details of the materials substitution and showing the results of the testing referred to in paragraph (b)(3) of this section. The records are to be maintained in accordance with regulations established by the Consumer Product Safety Commission (see § 1632.31 ) .