Occupational Noise-Induced Hearing Loss, before January 2, 1990

Policy

The WSIB will accept entitlement for occupational noise-induced hearing loss (NIHL) when it is the result of exposure to hazardous noise through employment in the province of Ontario and when both criteria outlined below exist.

Exposure Criteria

  1. There is a clear and adequate history of five or more years of exposure to hazardous noise, 90 decibels (dB) "A" scale, for eight hours per day, or equivalent as per section 139 of Ontario Regulation 488/01 under the Occupational Health and Safety Act.

Equivalent daily hazardous noise exposures per Ontario Regulation 488/01 (Occupational Health and Safety Act)
Sound level in decibels Duration - Hours per 24 hour day
90 8
92 6
95 4
97 3
100 2
102 1 1/2
105 1
110 1/2
115 ¼ or less
Over 115 No exposure
  1. The average hearing loss of the four speech frequency levels 500, 1,000, 2,000 and 3,000 Hertz in the American National Standards Institute (ANSI) or International Organization for Standardization (ISO) audiometer standards is 25 decibels in each ear.

Exception

Since individual susceptibility to noise varies, claims which do not meet the exposure criteria set out above are individually judged on their own merit having regard to the nature of the occupation, extent of exposure, and any other factors peculiar to the individual case.

Guidelines

The WSIB requires a minimum loss of 25 decibels in both ears as a result of occupational noise exposure in order to qualify for noise induced hearing loss entitlement.

Permanent disability

Entitlement to health care and/or permanent disability benefits will be considered:

  1. when the average hearing loss of the four speech frequency levels (500, 1,000, 2,000, and 3,000 Hertz) in the ANSI or ISO audiometer standards is at least 35 decibels in the worse ear and at least 25 decibels in the better ear, or
  2. for asymmetrical hearing loss when the average hearing loss is 35 decibels in at least one ear but less than 25 decibels in the other, and when the pattern of hearing loss is clearly consistent with occupational noise exposure.

Using the permanent disability rating schedule for hearing loss below, the decibel measurement of hearing loss is converted to a percentage, which represents the amount of permanent disability. The level of rating is not influenced by any improvement in hearing attained through use of a hearing aid(s).

Permanent disability entitlement is considered to begin on the date notification of the claim is received by the WSIB, however, an entitlement date may be altered if hearing loss prior to that date can be clinically established and confirmed by the adjudicator.

Entitlement under this policy is retroactive to June 3, 1988, or the date of the disability, whichever is later.

Out of province

If there is a history of out of province occupational noise exposure

  1. it is calculated as a percentage of the total exposure, and
  2. the total of the permanent disability award is reduced by this percentage

Non-compensable hearing loss

When a non-compensable hearing loss is identified, the worker's compensable degree of hearing loss will be estimated based on test results.

When the level of a pre-existing, non-compensable hearing loss is known, the permanent disability award will equal the entire hearing loss minus the percentage of the pre-existing non-compensable hearing loss, in accordance with the permanent disability rating schedule for hearing loss below.

Hearing loss permanent disability rating schedule

This schedule is used to determine the degree of permanent disability due to occupational NIHL, expressed as a percentage, where the hearing loss is greater than 35 decibels in at least one ear. To determine the percentage:

  1. Find worse ear dB loss on vertical axis (first column)
  2. Move right to find better ear dB loss on horizontal axis.

Where the hearing loss is less than 25 decibels in the better ear, the award is a single ear award, as outlined in the single ear award column.

The award for total noise-induced deafness in both ears is 30%.

Permanent disability award percentage based on decibel loss
Decibel (dB) loss Single ear award

27.5
to
32.4

(better ear)

32.5
to
37.4 

(better ear)

37.5
to
42.4 

(better ear)

42.5
to
47.4 

(better ear)

47.5
to
52.4 

(better ear)

52.5
to
57.4 

(better ear)

57.5
to
62.4 

(better ear)

62.5
to
72.4 

(better ear)

67.5
to
72.4 

(better ear)

72.5
to
77.4 

(better ear)

77.5
to
80.4 

(better ear)

35.0 to
37.4

(worse ear)

 0.4 1.4 2.4 N/A N/A N/A N/A N/A N/A N/A N/A N/A

37.5 to
42.4

(worse ear)

 0.7 1.7 2.7 4.2 N/A N/A N/A N/A N/A N/A N/A N/A

42.5 to
47.4

(worse ear)

 1.0 2.0 3.0 4.5 6.0 N/A N/A N/A N/A N/A N/A N/A

47.5 to
52.4

(worse ear)

 1.4 2.4 3.4 4.9 6.4 8.4 N/A N/A N/A N/A N/A N/A

52.5 to
57.4

(worse ear)

 1.8 2.8 3.8 5.3 6.8 8.8 10.8 N/A N/A N/A N/A N/A

57.5 to
62.4

(worse ear)

 2.3 3.3 4.3 5.8 7.3 9.3 11.3 13.8 N/A N/A N/A N/A

62.5 to
67.4

(worse ear)

 2.8 3.8 4.8 6.3 7.8 9.8 11.8 14.3 16.8 N/A N/A N/A

67.5 to
72.4

(worse ear)

 3.4 4.4 5.4 6.9 8.4 10.4 12.4 14.9 17.4 20.4 N/A N/A

72.5 to
77.4

(worse ear)

 4.0 5.0 6.0 7.5 9.0 11.0 13.0 15.5 18.0 21.0 24.0 N/A

77.5 to
80.0

(worse ear)

 5.0 6.0 7.0 8.5 10.0 12.0 14.0 16.5 19.0 22.0 25.0 30.0

NOTE

1. dB - decibel: measurement of sound intensity.
2. A presbycusis factor (degeneration of hearing due to aging) of 0.5 decibels is deducted for each year that the worker's age exceeds 60.

Date of accident

For NIHL claims, the date of accident is the date of NIHL diagnosis or the date of initial documented evidence for the hearing loss that led to the diagnosis, whichever is earlier (see, 11-01-04, Determining the Date of Injury).

For occupational noise-induced hearing loss post-January 2, 1990, see 16-01-04, Noise-induced Hearing Loss, on/after January 2, 1990.

Application date

This policy applies to all decisions made on or after July 20, 2023, for accidents occurring before January 2, 1990.

Document history

This document replaces 16-01-03 dated October 12, 2004.

This document was previously published as:
04-03-06 dated December 1, 1992.

References

Legislative authority

Workers' Compensation Act, R.S.O. 1980
Section 1(1)(a), 1(1)(n), 3(1), 40(1), 45(1), 45(3), 45(12), 52, 54, 122

Minute

Administrative
#5, July 17, 2023, page 619