Wisconsin Administrative Code › Department of Workforce Development › DWD 80-81 - Worker's Compensation › Chapter DWD 80 - Worker's Compensation › Section DWD 80.25 - Loss of hearing

Current through June 24, 2024
The department adopts the following standards for the
				  determination and evaluation of noise induced hearing loss, other occupational
				  hearing loss and accidental hearing loss:
(1) HARMFUL NOISE. Hearing loss resulting
				from hazardous noise exposure depends upon several factors, namely, the overall
				intensity (sound pressure level), the daily exposure, the frequency
				characteristic of the noise spectrum and the total lifetime exposure. Noise
				exposure level of 90 decibels or more as measured on the A scale of a sound
				level meter for 8 hours a day is considered to be harmful.
(2) MEASUREMENT OF NOISE. Noise shall be
				measured with a sound level meter which meets ANSI standard 1983 and shall be
				measured on the "A" weighted network for "slow response." Noise levels reaching
				maxima at intervals of one second or less shall be classified as being
				continuous. The measurement of noise is primarily the function of acoustical
				engineers and properly trained personnel. Noise should be scientifically
				measured by properly trained individuals using approved calibrated instruments
				which at the present time include sound level meters, octave band analyzers and
				oscilloscopes, the latter particularly for impact-type noises.
(3) MEASURE OF HEARING ACUITY. The use of
				pure tone air and bone conduction audiometry performed under proper testing
				conditions is recommended for establishing the hearing acuity of workers. The
				audiometer should be one which meets the specifications of ANSI standard
				53.6-1969 (4). The audiometer should be periodically calibrated. Preemployment
				records should include a satisfactory personal and occupational history as they
				may pertain to hearing status. Otological examination should be made where
				indicated.
(4) FORMULA FOR
				MEASURING HEARING IMPAIRMENT. For the purpose of determining the hearing
				impairment, pure tone air conduction audiometry is used, measuring all
				frequencies between 500 and 6,000 Hz. This formula uses the average of the 4
				speech frequencies of 500, 1,000, 2,000, and 3,000 Hz. Audiometric measurement
				for these 4 frequencies averaging 30 decibels or less on the ANSI calibration
				does not constitute any practical hearing impairment. A table for evaluating
				hearing impairment based upon the average readings of these 4 frequencies
				follows below. No deduction is made for presbycusis.
(5) DIAGNOSIS AND EVALUATION. The diagnosis
				of occupational hearing loss is based upon the occupational and medical
				history, the results of the otological and audiometric examinations and their
				evaluation.
(6) TREATMENT. There is
				no known medical or surgical treatment for improving or restoring hearing loss
				due to hazardous noise exposure. Hearing loss will be improved in
				non-occupational settings with the use of a hearing aid. Since a hearing aid
				relieves from the effect of injury the cost is compensable where prescribed by
				a physician.
(7) ALLOWANCE FOR
				TINNITUS. In addition to the above impairment, if tinnitus has permanently
				resulted due to work exposure, an allowance of 5% loss of hearing impairment
				for the affected ear or ears shall be computed.
(8) HEARING IMPAIRMENT TABLE.
Average Decibel Loss ANSI
Percent of Compensable
Hearing Impairment
Average Decibel Loss ANSI
Percent of Compensable
Hearing Impairment
30
0.0
62
51.2
31
1.6
63
52.8
32
3.2
64
54.4
33
4.8
65
56.0
34
6.4
66
57.6
35
8.0
67
59.2
36
9.6
68
60.8
37
11.2
69
62.4
38
12.8
70
64.0
39
14.4
71
65.6
40
16.0
72
67.2
41
17.6
73
68.8
42
19.2
74
70.4
43
20.8
75
72.0
44
22.4
76
73.6
45
24.0
77
75.2
46
25.6
78
76.8
47
27.2
79
78.4
48
28.8
80
80.0
49
30.4
81
81.6
50
32.0
82
83.2
51
33.6
83
84.8
52
35.2
84
86.4
53
36.8
85
88.0
54
38.4
86
89.6
55
40.0
87
91.2
56
41.6
88
92.8
57
43.2
89
94.4
58
44.8
90
96.0
59
46.4
91
97.6
60
48.0
92
99.2
61
49.6
93
100.0
(9)
				METHOD FOR DETERMINING PERCENT OF HEARING IMPAIRMENT.
(a) Obtain for each ear the average hearing
				level in decibels at the 4 frequencies, 500, 1,000, 2,000 and 3,000
				Hz.
(b) See Table for converting to
				percentage of hearing impairment in each ear.
(c) To determine the percentage of impairment
				for both ears, multiply the lesser loss by 5, add the greater loss and divide
				by 6. Following are examples of the calculation of hearing loss:
A.
Mild to Marked Bilateral Hearing
				Loss
500 Hz
1,000 Hz
2,000 Hz
3,000 Hz
Right Ear
15
25
45
55
Left Ear
30
45
60
85
1. Calculation
				of average hearing threshold level:
See
				  Image
2.
				Calculation of hearing disability:
Smaller number (better ear)
8% 5 = 40
Larger number (poorer ear)
40% 1 = 40
Total 80 ÷ 6 = 13.33% loss
Therefore, a person with the hearing threshold levels shown
				  in this audiogram would have a 13.33% hearing disability.
B.
Slight
				Bilateral Hearing Loss
500 Hz
1,000 Hz
2,000 Hz
3,000 Hz
Right Ear
15
15
20
30
Left Ear
25
30
35
40
1. Average
				hearing threshold level:
See
				  Image
Therefore, the hearing loss is 4.8% left ear
C.
Severe to Extreme
				Bilateral Hearing Loss
500 Hz
1,000 Hz
2,000 Hz
3,000 Hz
Right Ear
80
90
100
110
Left Ear
75
80
90
95
1. Average
				hearing threshold level (use 93 db maximal value) :
See
				  Image
2. Hearing
				handicap:
Smaller number (better ear)
88% × 5 = 440
Larger number (poorer ear)
100% × 1 = 100%
Total 540 × 6 = 90% loss
Therefore, the hearing handicap is 90%.