A licensed dispensing audiologist shall, upon the consummation of a sale of a hearing aid, keep and maintain records in the licensed dispensing audiologist’s office or place of business at all times and each such record shall be kept and maintained for a seven-year period. These records shall include:

1. (a) Results of test techniques as they pertain to fitting of the hearing aid.
2. (b) A copy of the written notice and the written receipt required by Section 2539.4 and the written recommendation and receipt required by Section 2539.6, when applicable.