The licensee or holder of a limited license who is engaged in the fitting and dispensing of hearing aids shall use appropriate testing procedures for a hearing aid fitting. The licensee or holder of a limited license shall perform the following minimum testing procedures on each client evaluated prior to the fitting of a hearing aid or hearing aids: Pure tone air conduction thresholds at 250 Hz, 500 Hz, 1,000 Hz, 2,000 Hz, 4,000 Hz, 6,000 Hz, and 8,000 Hz, including masking as needed, if the threshold between the ears differs, at any frequency, by: 40 decibels when using supra aural headphones; 60 decibels when using insert earphones, properly inserted; or Inter-octave frequencies that shall be tested if there is a difference of 15dB or greater between octave frequencies as specified under §B(1)(a) and (b) of this regulation; Pure tone bone conduction thresholds, including masking as needed, at 500 Hz, 1000 Hz, 2000 Hz, and 4000Hz; and Word recognition scores obtained using recorded word lists or monitored live voice. Presentation level shall be at least 40dB above speech recognition threshold or at least 5dB above the threshold at 2000Hz, or both, if within level of tolerance. The use of speech stimuli, such as speech in noise testing, is recommended before and after the fitting of the hearing aid. The use of probe microphone measurements are recommended to verify the audibility of speech at 50dB, 65dB, and 80dB input levels as well as MPO measurements to avoid damage to the peripheral auditory system and check comfort of the hearing aid users. The hearing aid dispenser shall: Maintain and retain all test results as part of a client’s record. Part or all of the tests may be performed by an otologist or clinical audiologist, but the test may not be more than 6 months old for the use of a hearing device fitting; and Provide to the client a copy of all: Test results; Recommendations; and Referrals. During the 2-year renewal, a hearing aid dispenser shall furnish evidence that each audiometer in use has been calibrated within the previous 12-month period. Before fitting or selling a hearing aid to a potential client, the licensee shall refer the client to a physician, preferably one specializing in the diseases of the ear, if the licensee determines that the client has any of the following conditions: Visible, congenital, or traumatic deformity of the ear; Acute drainage from the ear within the previous 90 days; Sudden or rapidly progressive hearing loss within the previous 90 days; Acute or chronic dizziness; Pain, discomfort, foreign body/material, or active drainage in the ear; Air-bone gap in excess of 15 decibels on more than one frequency; Evidence of congenital or traumatic deformity of the ear, not previously evaluated; Unilateral or asymmetrical hearing loss with a difference of greater than 15dB pure tone average between ears, or asymmetry greater than 15dB at 2 or more frequencies; or Visible evidence of cerumen (ear wax) accumulation or a foreign body in the ear canal.