Minnesota Legislature
Office of the Revisor of Statutes
Minnesota Administrative Rules
5223.0340 EAR.
Subpart 1.
General.
For permanent partial impairment to hearing, disability to the whole body is as provided in subparts 2 to 8. For hearing loss, the maximum disability of the whole body is 35 percent. Permanent partial impairment due to cosmetic disfigurement is rated as provided in part 5223.0650 and may be combined with ratings under this part as described in part 5223.0300, subpart 3, item E. Permanent partial impairment due to impairment of vestibular function is rated as provided in part 5223.0360, subpart 5, and may be combined with ratings under this part.
Subp. 2.
Standards for audiometric calibration and test environment.
To ensure accurate measurement of hearing loss, the standards in items A and B shall be observed in conducting the audiological evaluation required in subpart 4.
A.
The audiometer used to measure hearing loss shall be calibrated to meet the specifications of ANSI, S3.6-1969 (R 1973), Specifications for Audiometers, as incorporated by reference in part 5223.0300, subpart 4, item D. The following are also required:
(1)
biological or electroacoustical calibration checks of the audiometer shall be performed monthly;
(2)
electroacoustical calibration shall be performed annually to certify the audiometer to the ANSI standard in this item; and
Subp. 3.
Waiting period for final evaluation of hearing loss.
A waiting period of at least three months shall elapse between the date of the occurrence of the noise injury and the final evaluation of the permanent partial hearing loss.
Subp. 4.
Procedure for determining binaural hearing loss.
The calculation for the percent of binaural hearing loss is done with the worksheet provided in subpart 5 and consists of the steps in items A to F.
A.
For each ear, test the hearing threshold levels at the four frequencies of 500, 1,000, 2,000, and 3,000 Hertz as determined by pure tone air conduction testing.
B.
For each ear, determine the average four-frequency hearing level. The average four-frequency hearing level is one-fourth of the sum of the threshold levels at each of the four tested frequencies. The average four-frequency hearing level is expressed in decibels.
C.
For each ear, subtract 25 decibels from the average four-frequency hearing level for that ear. The remainder, expressed in decibels, is the adjusted average four-frequency hearing level.
D.
For each ear, multiply the adjusted average four-frequency hearing level by 1.5. The product is the monaural hearing loss, expressed as a percentage. A product less than zero percent is deemed to be zero. A product greater than 100 percent is deemed to be 100 percent.
E.
Considering both ears, compare the monaural hearing losses as determined in item D. The ear with the smaller monaural hearing loss is the better ear. The ear with the larger monaural hearing loss is the poorer ear.
F.
Multiply the monaural hearing loss of the better ear by five, add this product to the monaural hearing loss of the poorer ear, and divide the sum by six. The quotient is the binaural hearing loss, expressed as a percentage. The formula is:
| (5 x monaural hearing loss of better ear) | + | (monaural hearing loss of poorer ear) | |
|
_
6 |
= percent binaural hearing loss | ||
Subp. 5.
Worksheet for calculating percent of binaural hearing loss.
| Left Ear | Right Ear | |||
| Hertz | Threshold | Hertz | Threshold | |
| 500 | A. _ | 500 | A. _ | |
| 1,000 | B. _ | 1,000 | B. _ | |
| 2,000 | C. _ | 2,000 | C. _ | |
| 3,000 | D. _ | 3,000 | D. _ | |
| (A + B + C + D) ÷ 4 = | E. _ | (A + B + C + D) ÷ 4 = | E. _ | |
| E - 25 = (if < 0 use 0) | F. _ | E - 25 = (if < 0 use 0) | F. _ | |
| F x 1.5 = | G. _ | F x 1.5 = | G. _ | |
| Make G(1) the lesser of the two G's | ||||
| Make G(2) the greater of the two G's | ||||
| [[G(1) x 5] + G(2)] ÷ 6 = | H. _ | (binaural hearing loss) | ||
| H converts to whole body impairment as provided in subpart 6 | ||||
Subp. 6.
Procedure for determining disability due to binaural hearing loss.
The binaural hearing loss is translated to a percentage of disability of the whole body by the ear schedule in this subpart.
Ear Schedule
| Binaural Hearing Loss, Percent | Whole Body Disability, Percent |
| 0.0 - 1.7 | 0 |
| 1.8 - 4.2 | 1 |
| 4.3 - 7.4 | 2 |
| 7.5 - 9.9 | 3 |
| 10.0 - 13.1 | 4 |
| 13.2 - 15.9 | 5 |
| 16.0 - 18.8 | 6 |
| 18.9 - 21.4 | 7 |
| 21.5 - 24.5 | 8 |
| 24.6 - 27.1 | 9 |
| 27.2 - 30.0 | 10 |
| 30.1 - 32.8 | 11 |
| 32.9 - 35.9 | 12 |
| 36.0 - 38.5 | 13 |
| 38.6 - 41.7 | 14 |
| 41.8 - 44.2 | 15 |
| 44.3 - 47.4 | 16 |
| 47.5 - 49.9 | 17 |
| 50.0 - 53.1 | 18 |
| 53.2 - 55.7 | 19 |
| 55.8 - 58.8 | 20 |
| 58.9 - 61.4 | 21 |
| 61.5 - 64.4 | 22 |
| 64.6 - 67.1 | 23 |
| 67.2 - 70.0 | 24 |
| 70.1 - 72.8 | 25 |
| 72.9 - 75.9 | 26 |
| 76.0 - 78.5 | 27 |
| 78.6 - 81.7 | 28 |
| 81.8 - 84.2 | 29 |
| 84.3 - 87.4 | 30 |
| 87.5 - 89.9 | 31 |
| 90.0 - 93.1 | 32 |
| 93.2 - 95.7 | 33 |
| 95.8 - 98.8 | 34 |
| 98.9 - 100.0 | 35 |
Subp. 7.
Presbycusis.
The calculation of the binaural hearing loss shall not include an additional adjustment for presbycusis.
Statutory Authority:
MS s 176.105
History:
17 SR 3364
Published Electronically:
August 16, 2010
Official Publication of the State of Minnesota
Revisor of Statutes